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2.  Child Mortality Estimation: Estimating Sex Differences in Childhood Mortality since the 1970s 
PLoS Medicine  2012;9(8):e1001287.
Cheryl Sawyer uses new methods to generate estimates of sex differences in child mortality which can be used to pinpoint areas where these differences in mortality merit closer examination.
Introduction
Producing estimates of infant (under age 1 y), child (age 1–4 y), and under-five (under age 5 y) mortality rates disaggregated by sex is complicated by problems with data quality and availability. Interpretation of sex differences requires nuanced analysis: girls have a biological advantage against many causes of death that may be eroded if they are disadvantaged in access to resources. Earlier studies found that girls in some regions were not experiencing the survival advantage expected at given levels of mortality. In this paper I generate new estimates of sex differences for the 1970s to the 2000s.
Methods and Findings
Simple fitting methods were applied to male-to-female ratios of infant and under-five mortality rates from vital registration, surveys, and censuses. The sex ratio estimates were used to disaggregate published series of both-sexes mortality rates that were based on a larger number of sources. In many developing countries, I found that sex ratios of mortality have changed in the same direction as historically occurred in developed countries, but typically had a lower degree of female advantage for a given level of mortality. Regional average sex ratios weighted by numbers of births were found to be highly influenced by China and India, the only countries where both infant mortality and overall under-five mortality were estimated to be higher for girls than for boys in the 2000s. For the less developed regions (comprising Africa, Asia excluding Japan, Latin America/Caribbean, and Oceania excluding Australia and New Zealand), on average, boys' under-five mortality in the 2000s was about 2% higher than girls'. A number of countries were found to still experience higher mortality for girls than boys in the 1–4-y age group, with concentrations in southern Asia, northern Africa/western Asia, and western Africa. In the more developed regions (comprising Europe, northern America, Japan, Australia, and New Zealand), I found that the sex ratio of infant mortality peaked in the 1970s or 1980s and declined thereafter.
Conclusions
The methods developed here pinpoint regions and countries where sex differences in mortality merit closer examination to ensure that both sexes are sharing equally in access to health resources. Further study of the distribution of causes of death in different settings will aid the interpretation of differences in survival for boys and girls.
Please see later in the article for the Editors' Summary.
Editors' Summary
Background
In 2000, world leaders agreed to eradicate extreme poverty by 2015. To help track progress towards this global commitment, eight Millennium Development Goals (MDGs) were set. MDG 4, which aims to reduce child mortality, calls for a reduction in under-five mortality (the number of children who die before their fifth birthday) to a third of its 1990 level of 12 million by 2015. The under-five mortality rate is also denoted in the literature as U5MR and 5q0. Progress towards MDG 4 has been substantial, but with only three years left to reach it, efforts to strengthen child survival programs are intensifying. Reliable estimates of trends in childhood mortality are pivotal to these efforts. So, since 2004, the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) has used statistical regression models to produce estimates of trends in under-five mortality and infant mortality (death before age one year) from data about childbearing and child survival collected by vital registration systems (records of all births and deaths), household surveys, and censuses.
Why Was This Study Done?
In addition to estimates of overall childhood mortality trends, information about sex-specific childhood mortality trends is desirable to monitor progress towards MDG 4, although the interpretation of trends in the relative mortality of girls and boys is not straightforward. Newborn girls survive better than newborn boys because they are less vulnerable to birth complications and infections and have fewer inherited abnormalities. Thus, the ratio of infant mortality among boys to infant mortality among girls is greater than one, provided both sexes have equal access to food and medical care. Beyond early infancy, girls and boys are similarly vulnerable to infections, so the sex ratio of deaths in the 1–4-year age group is generally lower than that of infant mortality. Notably, as living conditions improve in developing countries, infectious diseases become less important as causes of death. Thus, in the absence of sex-specific differences in the treatment of children, the sex ratio of childhood mortality is expected be greater than one and to increase as overall under-five mortality rates in developing countries decrease. In this study, the researcher evaluated national and regional changes in the sex ratios of childhood mortality since the 1970s to investigate whether girls and boys have equal access to medical care and other resources.
What Did the Researcher Do and Find?
The researcher developed new statistical fitting methods to estimate trends in the sex ratio of mortality for infants and young children for individual countries and world regions. When considering individual countries, the researcher found that for 92 countries in less developed regions, the median sex ratio of under-five mortality increased between the 1970s and the 2000s, in line with the expected changes just described. However, the average sex ratio of under-five mortality for less developed regions, weighted according to the number of births in each country, did not increase between the 1970s and 2000s, at which time the average under-five mortality rate of boys was about 2% higher than that of girls. This discrepancy resulted from India and China—the two most populous developing countries—having sex ratios for both infant and under-five mortality that remained constant or declined over the study period and were below one in the 2000s, a result that indicates excess female mortality. In China, for example, infant mortality was found to be 12% higher for boys than for girls in the 1970s, but 24% lower for boys than for girls in the 2000s. Finally, although in the less developed regions (excluding India and China) girls went from having a slight survival disadvantage at ages 1–4 years in the 1970s, on average, to having a slight advantage in the 2000s, girls remained more likely to die than boys in this age group in several Asian and African countries.
What Do These Findings Mean?
Although the quality of the available data is likely to affect the accuracy of these findings, in most developing countries the ratio of male to female under-five mortality has increased since the 1970s, in parallel with the decrease in overall childhood mortality. Notably, however, in a number of developing countries—including several each in sub-Saharan Africa, northern Africa/western Asia, and southern Asia—girls have higher mortality than boys at ages 1–4 years, and in India and China girls have higher mortality in infancy. Thus, girls are benefitting less than boys from the overall decline in childhood mortality in India, China, and some other developing countries. Further studies are needed to determine the underlying reasons for this observation. Nevertheless, the methods developed here to estimate trends in sex-specific childhood mortality pinpoint countries and regions where greater efforts should be made to ensure that both sexes have equal access to health care and other important resources during early life.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001287.
This paper is part of a collection of papers on Child Mortality Estimation Methods published in PLOS Medicine
The United Nations Childrens Fund works for children's rights, survival, development, and protection around the world; it provides information on Millennium Development Goal 4, and its Childinfo website provides detailed statistics about child survival and health, including a description of the United Nations Inter-agency Group for Child Mortality Estimation; the 2011 UN IGME report Levels & Trends in Child Mortality is available
The World Health Organization also has information about Millennium Development Goal 4 and provides estimates of child mortality rates (some information in several languages)
Further information about the Millennium Development Goals is available
A 2011 report by the United Nations Department of Economic and Social Affairs entitled Sex Differentials in Childhood Mortality is available
doi:10.1371/journal.pmed.1001287
PMCID: PMC3429399  PMID: 22952433
3.  Mortality of a cohort of tin miners 1941-86. 
The mortality patterns of United Kingdom tin miners were examined in relation to calendar period and duration of underground work with particular attention to lung cancer and exposure to radon. Subjects were all men who had worked for at least one year between 1941 and 1984 at one of two United Kingdom tin mines and for whom a complete work history could be constructed from mine records. Standardised mortality ratios (SMRs) were calculated using national (England and Wales) rates. The pattern of SMRs in relation to potential explanatory variables was analysed using Poisson regression methods. Mortalities from lung cancer and silicosis (including silicotuberculosis) were significantly raised and showed a significant relation with duration of underground work (mortality from stomach cancer was raised in both underground and surface workers, but not significantly). Excess mortality from silica related disease declined steeply from 35% among workers first exposed before 1920 to 1% among those first exposed after 1950. Thirteen surface workers with known exposure to arsenic had high rates of lung and stomach cancer. The SMR for lung cancer showed a consistent pattern in relation to duration of underground exposure, rising from 83 (observed/expected = 8/9.6) for surface workers (without exposure to arsenic) to 447 (15/3.4) for workers with more than 30 years underground exposure. Examination of the SMR for lung cancer by total underground exposure, age, and time since last exposure gave rise to a model for the expression of risk which depends only on total exposure and time since exposure. The fitted model implies that the effect of exposure to radon in a given year has no effect on risk for 10 years, then rapidly rises to a maximum from which the excess risk then declines, halving every 4.3 years. There were no direct measurements of historic radon levels. A conservative estimate based on measurements taken since 1969 by the National Radiological Protection Board and the Mines and Quarries Inspectorate is that the annual dose to an underground worker was about 10 working level months (WLM). Given this assumption, the risk/exposure slope implied by the present data, and the model fitted to it, was somewhat lower than that given in the fourth Committee on the Biological Effects of Ionisation Radiation (BEIR IV) report (about 40% lower for lifetime exposures). The present data also imply different risks depending on the age at exposure, with relatively higher lifetime risks for exposure at older ages, and relatively lower risks for exposures at younger ages. In conclusion, there was a clear relation between exposure to radon and death from lung cancer. The relative risk of lung cancer due to exposure to radon was not constant in cessation of exposure. The lifetime excess risk of lung cancer implied by these data for 40 years exposure at the current statutory limit of four WLM a year starting at age 20, was about 8% (79 excess deaths per 1000 exposed), assuming average smoking habits among the exposed workers. Control of dust concentrations in the mines has substantially reduced--and may have eliminated--direct mortality from silica related disease.
PMCID: PMC1012024  PMID: 2223659
4.  Factors Associated with American Board of Medical Specialties Member Board Certification among US Medical School Graduates 
Context
Certification by an American Board of Medical Specialties (ABMS) member board is emerging as a measure of physician quality.
Objective
To identify demographic and educational factors associated with ABMS-member-board certification of US medical graduates.
Design, Setting, Participants
Retrospective study of a national cohort of 1997–2000 US medical graduates, grouped by specialty choice at graduation and followed up through March 2, 2009. In separate multivariable logistic regression models for each specialty category, factors associated with ABMS-member-board certification were identified.
Main Outcome Measure
ABMS-member-board certification
Results
Of 42 440 graduates in the study sample, 37 054 (87.3%) were board certified. Graduates in all specialty categories with first-attempt passing scores in the highest tertile (vs first-attempt failing scores) on US Medical Licensing Examination Step 2 Clinical Knowledge were more likely to be board certified; adjusted odds ratios (aOR) varied by specialty category with the lowest odds for emergency medicine (87.4% vs 73.6%; aOR, 1.82; 95% confidence interval [CI], 1.03–3.20) and highest odds for radiology (98.1% vs 74.9%; aOR, 13.19; 95% CI, 5.55–31.32). In each specialty category except family medicine, graduates self-identified as underrepresented racial/ethnic minorities (vs white) were less likely to be board certified, ranging from 83.5% vs 95.6% in the pediatrics category (aOR, 0.44; 95% CI, 0.33–0.58) to 71.5% vs 83.7% in the other non-generalist specialties category (aOR, 0.79; 95% CI, 0.64–0.96). With each $50 000 unit increase in debt (vs no debt), graduates choosing obstetrics/gynecology were less likely to be board certified (aOR, 0.89; 95% CI, 0.83–0.96), and graduates choosing family medicine were more likely to be board certified (aOR 1.13; 95% CI, 1.01–1.26).
Conclusion
Demographic and educational factors were associated with board certification among US medical graduates in every specialty category examined; findings varied among specialty categories.
doi:10.1001/jama.2011.1099
PMCID: PMC3217584  PMID: 21900136
5.  Educational treasures in Radiology: A free online program for Radiology Boards preparation 
Purpose
An objective tool is desired, which optimally prepares for Radiology boards examination. Such program should prepare examinees with pertinent radiological contents and simulations as expected in the real examination.
Background
Many countries require written boards examinations for Radiology certification eligibility. No objective measure exists to tell if the examinee is ready to pass the exam or not. Time pressure and computer environment might be unfamiliar to examinees. Traditional preparation lectures don't simulate the "real" Radiology exam because they don't provide the special environment with multiple choice questions and timing.
Materials and Methods
This online program consists of 4 parts. The entry section allows to create questions with additional fields for comprehensive information. Sections include Pediatrics/Mammography/GI/IR/Nucs/Thoracic/Musculoskeletal/GU/Neuro/Ultrasound/Cardiac/OB/GYN and Miscellaneous. Experienced radiologists and educators evaluate and release/delete these entries in the administrator section. In the exam section users can create (un)timed customized exams for individual needs and learning pace. Exams can either include all sections or only specific sections to gear learning towards areas with weaker performance. Comprehensive statistics unveil the user's strengths and weaknesses to help focussing on "weak" areas. In the search section a comprehensive search and review can be performed by searching the entire database for keywords/topics or only searching within specific sections.
Conclusion
www.RadiologyBoards.org is a new working concept of Radiology boards preparation to detect and improve the examinee's weaknesses and finally to increase the examinee's confidence level for the final exam. It is beneficial for Radiology residents and also board certified radiologists to refresh/maintain radiological knowledge.
doi:10.3941/jrcr.v5i2.732
PMCID: PMC3303428  PMID: 22470779
Radiology boards; Radiology exam; exam preparation; Radiology examination
6.  A Survey of the Methods Developed in the National Coal Board's Pneumoconiosis Field Research for Correlating Environmental Exposure with Medical Condition 
The correlation of the medical and environmental data (i.e. the derivation of the dosage-response relationship) in a study such as the National Coal Board's Pneumoconiosis Field Research (P.F.R.) is subject to many complicating factors compared with the more conventional types of biological assay. Several methods have been developed within the Research to overcome these difficulties, and the new procedures are described. Each is concerned with the estimation of the direct relation between the radiological abnormality associated with simple pneumoconiosis and some single measure of the past hazard, but the basic techniques are sufficiently general to be applicable in other fields of study.
The first development involves the definition of an underlying continuous scale of radiological abnormality. This prepares the way for the derivation of the “quantitative” relation between exposure and response, to replace the “semi-quantal” relation which is inherent in the use of a small number of discrete categories of radiological abnormality. The effect of errors of observation of dosage and response on the corresponding quantitative and quantal relationships is then determined.
The second development concerns the use of a “multi-dimensional” representation of past hazard. Most of the men under observation had worked in a number of different mining occupations before their first chest radiograph was taken, but this exposure cannot be assessed in terms of dust concentrations, for which reliable data are not available. Nevertheless, it is shown that past hazard can usefully be represented by three “dimensions” corresponding to the periods spent in three main types of environment—(a) the coal-face (coal-getting shift), (b) the coal-face (preparation shift) and (c) elsewhere underground. Each man's past exposure up to the time of his first chest radiograph can be expressed in terms of these three dimensions and the effect of each environment separately can be determined.
The third development extends the multi-dimensional approach to cover not only the working history before the first medical examination, but also the recorded exposure (in terms of measured dust concentrations), to which each man has been subject between the first and subsequent “follow-up” surveys. This measured exposure is regarded as one dimension of the man's total exposure up to the time of his second (or later) examination, and it is possible in this way to determine the direct relation between radiological abnormality and measured exposure, even when this component represents only part of the total hazard to which the man has been subject.
The application of the methods is illustrated by the analysis of some of the data which have been obtained in the Pneumoconiosis Field Research.
PMCID: PMC1038147  PMID: 13698432
7.  Recurrent Dislocation of the Shoulder Joint 
Dr. Anthony F. DePalma is shown. Photograph provided with kind permission of the Art Committee of Thomas Jefferson University, Philadelphia, PA.
Dr. DePalma was the first editor of Clinical Orthopaedics and Related Research, established by the recently formed Association of Bone and Joint Surgeons. The idea of forming the Association of Bone and Joint surgeons had been conceived by Dr. Earl McBride of Oklahoma City in 1947, and organized by a group of twelve individuals (Drs. Earl McBride, Garrett Pipkin, Duncan McKeever, Judson Wilson, Fritz Teal, Louis Breck, Henry Louis Green, Howard Shorbe, Theodore Vinke, Paul Williams, Eugene Secord, and Frank Hand) [9]. The first organizational meeting was held in conjunction with the 1949 Annual Meeting of the AAOS [9] and the first annual meeting held April 1–2, 1949 in Oklahoma City. Drs. McBride and McKeever invited Dr. DePalma to attend that meeting and join the society. According to DePalma, “Even at this small gathering, there were whisperings of the need of another journal to provide an outlet for the many worthy papers written on clinical and basic science subjects” [7]. The decision to form a new journal was finalized in 1951, and Drs. DePalma and McBride signed a contract with J.B. Lippincott Company. Dr. DePalma was designated Editor-in-Chief, and the journal became a reality in 1953 with the publication of the first volume. From the outset he established the “symposium” as a unique feature, in which part of the articles were devoted to a particular topic. Dr. DePalma served as Editor for 13 years until 1966, when he resigned the position and recommended the appointment of Dr. Marshall R. Urist. At his retirement, Clinical Orthopaedics and Related Research was well established as a major journal.
Dr. Anthony F. DePalma was born in Philadelphia in 1904, the son of immigrants from Alberona in central Foggia, Italy [1]. He attended the University of Maryland for his premedical education, then Jefferson Medical College, from which he graduated in 1929. He then served a two-year internship (common at the time) at Philadelphia General Hospital. Jobs were scarce owing to the Depression, and he felt fortunate to obtain in 1931 a position as assistant surgeon at the Coaldale State Hospital, in Coaldale, Pennsylvania, a mining town. However, he became attracted to orthopaedics and looked for a preceptorship (postgraduate training in specialties was not well developed at this time before the establishments of Boards). In the fall of 1932, he was appointed as a preceptor at the New Jersey Orthopaedic Hospital, an extension of the New York Orthopaedic Hospital. In 1939 he acquired Board certification (the first board examination was offered in 1935 for a fee of $25.00 [2]) and was appointed to the NJOH staff [1].
Dr. DePalma volunteered for military service in 1942, and served first at the Parris Island Naval Hospital in South Carolina, then on the Rixey, a hospital ship. In addition to serving to evacuate casualties to New Zealand, his ship was involved in several of the Pacific island assaults (Guam, Leyte, Okinawa). In 1945, he was assigned to the Naval Hospital in Philadelphia [1].
On his return to Philadelphia, he contacted staff members at Jefferson Medical College, including the Chair, Dr. James Martin, and became good friends with Dr. Bruce Gill (a professor of Orthopaedics at the University of Pennsylvania, and one of the earliest Presidents of the AAOS). After he was discharged from the service, he joined the staff of the Department of Orthopaedic Surgery at Jefferson, where he remained the rest of his career. He succeeded Dr. Martin as Chair in 1950, a position he held until 1970 when he reached the mandatory retirement age of 65. He closed his practice and moved briefly to Pompano Beach, Florida, but the lure of academia proved too powerful, and in January, 1971, he accepted the offer to develop a Division of Orthopaedics at the New Jersey College of Medicine and became their Chair. He committed to a five-year period, and then again moved to Pompano Beach, only to take the Florida State Boards and open a private practice in 1977. His practice grew, and he continued that practice until 1983 at the age of nearly 79. Even then he continued to travel and lecture [1].
We reproduce here four of his many contributions on the shoulder. The first comes from his classic monograph, “Surgery of the Shoulder,” published by J. B. Lippincott in 1950 [2]. In this article he describes the evolutionary development of the shoulder, focusing on the distinction between various primates, and relates the anatomic changes to upright posture and prehensile requirements. The remaining three are journal articles related to frozen shoulder [1], recurrent dislocation [3], and surgical anatomy of the rotator cuff [6], three of the most common shoulder problems then and now. He documented the histologic inflammation and degeneration in various tissues including the coracohumeral ligaments, supraspinatus tendon, bursal wall, subscapularis musculotendinous junction, and biceps tendon. Thus, the problem was rather more global than localized. He emphasized, “Manipulation of frozen shoulders is a dangerous and futile procedure.” For recurrent dislocation he advocated the Magnuson procedure (transfer of the subscapularis tendon to the greater tuberosity) to create a musculotendinous sling. All but two of 23 patients he treated with this approach were satisfied with this relatively simple procedure. (Readers will note the absence of contemporary approaches to ascertain outcomes and satisfaction. The earliest outcome musculoskeletal measures were introduced in the 60s by Larson [11] and then by Harris [10], but these instruments were physician-generated and do not reflect the rather more rigorously validated patient-generated outcome measures we use today. Nonetheless, the approach used by Dr. DePalma reflected the best existing standards of reporting results.) Dr. DePalma’s classic article, “Surgical Anatomy of the Rotator Cuff and the Natural History of Degenerative Periarthritis,” [6] reflected his literature review and dissections of 96 shoulders from 50 individuals “unaware of any (shoulder) disability” and mostly over the age of 40. By the fifth decade, most specimens began to show signs of rotator cuff tearing and he found complete tears in nine specimens from “the late decades.” He concluded,
“Based on the…observations, one can reasonably construct the natural history of periarthritis of the shoulder. It is apparent that aging is an important etiological factor, and with aging certain changes take place in the connective tissue elements of the musculotendinous cuff…it is also apparent that in slowly developing lesions of this nature compensating adjustments in the mechanics of the joint take place so that severe alterations in the mechanics of the joint do not appear. However, one must admit that such a joint is very vulnerable and, if subjected to minor trauma, the existing degenerative lesion would be extended and aggravated.”
Thus, he clearly defined the benign effects of rotator cuff tear in many aging individuals, but also the potential to create substantial pain and disability.
Dr. DePalma was a prolific researcher and writer. In addition to his “Surgery of the Shoulder,” he wrote three other books, “Diseases of the Knee: Management in Medicine and Surgery” (published by J.B. Lippincott in 1954) [4], “The Management of Fractures and Dislocations” (a large and comprehensive two volume work published by W.B. Saunders in 1959, and going through 5 reprintings) [5], and “The Intervertebral Disc” (published by W.B. Saunders in 1970, and written with his colleague, Dr. Richard Rothman) [8]. PubMed lists 62 articles he published from 1948 until 1992.
We wish to pay tribute to Dr. DePalma for his vision in establishing Clinical Orthopaedics and Related Research as a unique journal and for his many contributions to orthopaedic surgery.
References
DePalma A. Loss of scapulohumeral motion (frozen shoulder). Ann Surg. 1952;135:193–204.DePalma AF. Origin and comparative anatomy of the pectoral limb. In: DePalma AF, ed. Surgery of the Shoulder. Philadelphia: JB Lippincott; 1950:1–14.DePalma AF. Recurrent dislocation of the shoulder joint. Ann Surg. 1950;132:1052–1065.DePalma AF. Diseases of the Knee: Management in Medicine and Surgery. Philadelphia, PA: JB Lippincott Company; 1954.DePalma AF. The Management of Fractures and Dislocations—An Atlas. Philadelphia: WB Saunders Company; 1959.DePalma AF. Surgical anatomy of the rotator cuff and the natural history of degenerative periarthritis. Surg Clin North Am. 1963;43:1507–1520.DePalma AF. A lifetime of devotion to the Janus of orthopedics. Bridging the gap between the clinic and laboratory. Clin Orthop Relat Res. 1991;265:146–169.DePalma AF, Rothman RH. The Intervertebral Disc. Philadelphia: WB Saunders Company; 1970.Derkash RS. History of the Association of Bone and Joint Surgeons. Clin Orthop Relat Res. 1997;337:306–309.Harris WH. Traumatic arthritis of the hip after dislocation and acetabular fractures: treatment by mold arthroplasty. An end-result study using a new method of result evaluation. J Bone Joint Surg Am. 1969;51:737–755.Larson CB. Rating scale for hip disabilities. Clin Orthop Relat Res. 1963;31:85–93.
doi:10.1007/s11999-007-0105-3
PMCID: PMC2505210  PMID: 18264840
8.  Dose exposure in the ITALUNG trial of lung cancer screening with low-dose CT 
The British Journal of Radiology  2012;85(1016):1134-1139.
Few data are available on the effective dose received by participants in lung cancer screening programmes with low-dose CT (LDCT). We report the collective effective dose delivered to 1406 current or former smokers enrolled in the ITALUNG trial who completed 4 annual LDCT examinations and related further investigations including follow-up LDCT, 2-[18F]flu-2-deoxy-d-glucose positron emission tomography (FDG-PET) or CT-guided fine needle aspiration biopsy (FNAB). Using the air CT dose index and Monte Carlo simulations on an anthropomorphic phantom, the whole-body effective dose associated with LDCT was determined for the eight CT scanners used in the trial. A value of 7 mSv was assigned to FDG-PET while the measured mean effective dose of CT-guided FNAB was 1.5 mSv. The mean collective effective dose in the 1406 subjects ranged between 8.75 and 9.36 Sv and the mean effective dose to the single subject over 4 years was between 6.2 and 6.8 mSv (range 1.7–21.5 mSv) according to the cranial–caudal length of the LDCT volume. 77.4% of the dose was owing to annual LDCT and 22.6% to further investigations. Considering the nominal risk coefficients for stochastic effects after exposure to low-dose radiation according to the National Radiological Protection Board, International Commission on Radiological Protection (ICRP) 60, ICRP103 and Biological Effects of Ionizing Radiation VII, the mean number of radiation-induced cancers ranged between 0.12 and 0.33 per 1000 subjects. The individual effective dose to participants in a 4-year lung cancer screening programme with annual LDCT is very low and about one-third of the effective dose that is associated with natural background radiation and diagnostic radiology in the same time period.
doi:10.1259/bjr/20711289
PMCID: PMC3587091  PMID: 21976631
9.  President Clinton's managed competition proposal. 
In the search for fairness of access to health care, value for the money spent, and high quality of patient care, the United States has vacillated between advocacy of government regulations (the 1970s) and of market-driven, pro-competitive (1980s) approaches. The possible enactment of President Clinton's health reform plan with a managed-care strategy (1990s) calls for paying physicians and other providers in a manner that often induces them to minimize the provision of services to patients per episode of illness. This article discusses the impact of such legislation on patients, physicians, and other providers. It then argues that the President's managed competition approach, which micromanages health-care services, will fail except by concurrently implementing his proposed National Health Board's global budgetary concept. The major reason is that health reform for the 36.6 million uninsured Americans, who are mostly the working poor and their dependents, is only practical and affordable if stringent policies are adopted that reorganize available health-care resources and simultaneously implement cost-containment constraints.
PMCID: PMC2571896  PMID: 8478966
10.  Factors predisposing to the development of progressive massive fibrosis in coal miners. 
Altogether 238 759 miners employed by the National Coal Board were examined in the third of the Board's radiological surveys from 1969 to 1973 inclusive. Excluding those diagnosed as having progressive massive fibrosis (PMF) on that occasion, 210 847 were in collieries still operating at the time of the fourth survey four to five years later 132 728 attended for radiography at the same colliery on the second occasion, and were used to study the attack rate of PMF. In all groups in the age range 35-54 and having category 2 simple pneumoconiosis (SPN) or less, 80% or more had a second radiograph. It was found that the probability of developing PMF increased sharply with rising category of SPN; however, half the cases occurred in men having SPN categories 0 or 1, who were in the majority. Current coalface work had no significant effect on the attack rate. Age increased the attack rate of PMF within each major SPN category (0, 1, 2, and 3), especially the higher categories. All or part of this effect may have been due to the fact that SPN in younger men with categories 1 and 2 tends to lie in the lower range within these categories. Similarly, a lower distribution of SPN within each category associated with a low overall local prevalence may account wholly or in part for the great difference between the attack rates of PMF supervening on each category of SPN in Scotland and South Wales. The rank (quality) of coal mined had no effect on the attack rate.
PMCID: PMC1069281  PMID: 7317294
11.  The Study of Observer Variation in the Radiological Classification of Pneumoconiosis 
In a long-term investigation such as the National Coal Board's Pneumoconiosis Field Research (P.F.R.), it is essential to establish satisfactory and stable procedures for making the necessary observations and measurements. It is equally important regularly to apply suitable methods of checking the accuracy and consistency of the various observations and measurements. One aspect of vital importance in the P.F.R. is the classification of the series of chest radiographs taken, at intervals, of all the men under observation. This is inevitably a subjective process, and (as with other similar fields of work) it is desirable to obtain some understanding of the basic process behind the operation. This can usefully be done by the help of “models” designed to describe the process, if necessary in simplified terms. The problem of the radiological classification of pneumoconiosis has been studied hitherto in terms of coefficients of disagreement (inter-observer variation) and inconsistency (intra-observer variation), but for various reasons the method was not considered entirely satisfactory. New methods of approach were therefore developed for studying the performance of the two doctors responsible for the film reading in the Research, and two distinct “models” were derived. The advantages and disadvantages of each are described in the paper, together with the applications of the two models to the study of some of the problems arising in the course of the investigation.
The first model is based on the assumption that if a film is selected at random from a batch representing a whole colliery population, and that if the film is of “true” category i, the chance of its being read as another category (j) is a constant, Pij, which depends upon the observer concerned, the particular batch of films being read, and the values of i and j. This model enables the performance of the readers to be monitored satisfactorily, and it has also been used to investigate different methods for arriving at an agreed, or “definitive”, assessment of radiological abnormality. The Pij model suffers from the disadvantage of applying only to “average” films, and the assumptions made are such that it manifestly does not provide an entirely realistic representation of the reading process on any particular film.
The second “improved” model was therefore developed to overcome this criticism. Briefly, it is considered that each film is representative of a unique degree of abnormality, located on a continuum, or abnormality scale, which covers the whole range of simple pneumoconiosis. The scale of abnormality is then chosen in such a way that, whatever the true degree of abnormality of the film, the observer's readings will be normally distributed about the true value with constant bias and variability at all points along the scale. The very large number of readings available has been analysed to determine the optimum positions of the category boundaries on the abnormality scale and in this way the scale has been unambiguously defined. The model enables the routine reading standards to be monitored, and it has also been used to investigate the underlying distribution of abnormality at individual collieries. Its chief disadvantage is the extensive computational work required.
The “fit” of both models to the data collected in the Research is shown to be satisfactory and on balance it appears that both have applications in this field of study. The method chosen in any given circumstance will depend upon the particular requirement and the facilities available for computational work.
PMCID: PMC1038082  PMID: 13698433
12.  TME10/380: Remote Transmission of Radiological Images by means of Intranet/Internet Technology 
Journal of Medical Internet Research  1999;1(Suppl 1):e117.
At the Istituto Nazionale Neurologico C. Besta in Milano a network architecture has been developed to connect computers and diagnostic modalities, based on Intranet technology in order to allow the hospital to have an external access through the Internet. The Internet technology has become the "glue" that allows to link different computers and to develop applications able to work independently from the hardware/software platform. Using a PACS (Picture Archiving and Communication System) system integrated to the diagnostic modalities by means of the standardized DICOM image format, the digital radiological images can be transferred, displayed and processed on special visualization workstations all around the hospital. From the workstations the same images can be transferred in DICOM format to a teleconsulting workstation. In fact the hospital is involved in a national project for the remote connection between many Italian hospitals. This national network is linked to already developed regional networks like the Toscana MAN and the ATM Sirius Network. Some links are performed directly in ATM (155 Mbps), others are based on CDN (Direct Numerical Connection, 2Mbps), others are simply based on ISDN connections. The system allows to make it simpler and faster the already established daily exchange of radiological reports between the involved hospitals, especially from Istituto Nazionale Neurologico and Istituto Nazionale deiTumori. All the actions performed by the radiologist are translated by the software into "events" and replied to the remote workstation and vice-versa. In this way the radiologists can see each others, speak together and act in real time on a common "board" of diagnostic images, each one with his own pointer. The adopted technology is evolving on a system based on a web architecture and Java applications, useful for small clinical centers not endowed with expensive information systems. These centers will be able to get consulting performances by the excellence centers, making available accurate diagnoses and therapy protocols.
doi:10.2196/jmir.1.suppl1.e117
PMCID: PMC1761785
Web; Booking
13.  Prostate cancer mortality risk in relation to working underground in the Wismut cohort study of German uranium miners, 1970–2003 
BMJ Open  2012;2(3):e001002.
Objective
A recent study and comprehensive literature review has indicated that mining could be protective against prostate cancer. This indication has been explored further here by analysing prostate cancer mortality in the German ‘Wismut’ uranium miner cohort, which has detailed information on the number of days worked underground.
Design
An historical cohort study of 58 987 male mine workers with retrospective follow-up before 1999 and prospective follow-up since 1999.
Setting and participants
Uranium mine workers employed during the period 1970–1990 in the regions of Saxony and Thuringia, Germany, contributing 1.42 million person-years of follow-up ending in 2003.
Outcome measure
Simple standardised mortality ratio (SMR) analyses were applied to assess differences between the national and cohort prostate cancer mortality rates and complemented by refined analyses done entirely within the cohort. The internal comparisons applied Poisson regression excess relative prostate cancer mortality risk model with background stratification by age and calendar year and a whole range of possible explanatory covariables that included days worked underground and years worked at high physical activity with γ radiation treated as a confounder.
Results
The analysis is based on miner data for 263 prostate cancer deaths. The overall SMR was 0.85 (95% CI 0.75 to 0.95). A linear excess relative risk model with the number of years worked at high physical activity and the number of days worked underground as explanatory covariables provided a statistically significant fit when compared with the background model (p=0.039). Results (with 95% CIs) for the excess relative risk per day worked underground indicated a statistically significant (p=0.0096) small protective effect of −5.59 (−9.81 to −1.36) ×10−5.
Conclusion
Evidence is provided from the German Wismut cohort in support of a protective effect from working underground on prostate cancer mortality risk.
Article summary
Article focus
Prostate cancer mortality in the Wismut cohort of German uranium miners in relation to time spent working underground and the time worked at high physical activity.
Key messages
Evidence is provided from the German Wismut cohort in support of a protective effect from working underground on prostate cancer mortality risk.
Strengths and limitations of this study
The Wismut study is currently the largest Uranium miner cohort.
There is detailed information on the time spent working underground and on other relevant occupational covariables.
However, there is no information on whether the shifts worked were early, late or at night.
doi:10.1136/bmjopen-2012-001002
PMCID: PMC3371580  PMID: 22685223
14.  Residential mobility among foreign-born persons living in Sweden is associated with lower mortality 
Clinical Epidemiology  2010;2:187-194.
There have been few longitudinal studies on the effect of within-country mobility on patterns of mortality in deceased foreign-born individuals. The results have varied; some studies have found that individuals who move around within the same country have better health status than those who do not change their place of residence. Other studies have shown that changing one’s place of residence leads to more self-reported health problems and diseases. Our aim was to analyze the pattern of mortality in deceased foreign-born persons living in Sweden during the years 1970–1999 in relation to distance mobility. Data from Statistics Sweden and the National Board of Health and Welfare was used, and the study population consisted of 281,412 foreign-born persons aged 16 years and over who were registered as living in Sweden in 1970. Distance mobility did not have a negative effect on health. Total mortality was lower (OR 0.71; 95% CI 0.69–0.73) in foreign-born persons in Sweden who had changed their county of residence during the period 1970–1990. Higher death rates were observed, after adjustment for age, in three ICD diagnosis groups “Injury and poisoning”, “External causes of injury and poisoning”, and “Diseases of the digestive system” among persons who had changed county of residence.
PMCID: PMC2943194  PMID: 20865116
residential mobility; health; foreign-born; immigrant; Sweden; mortality
15.  Assessment of Radiation doses to Paediatric Patients in Computed Tomography Procedures 
Polish Journal of Radiology  2014;79:344-348.
Summary
Background
The use of pediatric CT that had recently emerged as a valuable imaging tool has increased rapidly with an annual growth estimated at about 10% per year. Worldwide, there is a remarkable increase in the number of CT examinations performed. The purposes of this study are to: (i) to measure the radiation dose and estimate the effective doses to pediatric patients during CT for chest, abdomen and brain.
Material/Methods
A total of 182 patients were investigated. CT scanners that participated in this study are helical CT scanners (64 slices, 16 slices and dual slices). Organ and surface dose to specific radiosensitive organs were estimated by using software from National Radiological Protection Board (NRPB).
Results
For all patients, the age was ranged between 1.12 month–10.0 years while the weight was ranged between 5.0 kg to 29.0 kg. The DLP was 320.58 mGy·cm, 79.93 mGy·cm, 66.63 mGy·cm for brain, abdomen and chest respectively. The effective dose was, 2.05, 1.8, 1.08 mSv for brain, abdomen and chest respectively.
Conclusions
The patient dose is independent of CT modality and depends on operator experience and CT protocol. The study has shown a great need for referring criteria, continuous training of staff in radiation protection concepts. Further studies are required in order to establish a reference level in Sudan.
doi:10.12659/PJR.890806
PMCID: PMC4186214  PMID: 25289112
Dose-Response Relationship; Radiation; Relative Biological Effectiveness; Tomography Scanners; X-Ray Computed
16.  National Mesothelioma Virtual Bank: A standard based biospecimen and clinical data resource to enhance translational research 
BMC Cancer  2008;8:236.
Background
Advances in translational research have led to the need for well characterized biospecimens for research. The National Mesothelioma Virtual Bank is an initiative which collects annotated datasets relevant to human mesothelioma to develop an enterprising biospecimen resource to fulfill researchers' need.
Methods
The National Mesothelioma Virtual Bank architecture is based on three major components: (a) common data elements (based on College of American Pathologists protocol and National North American Association of Central Cancer Registries standards), (b) clinical and epidemiologic data annotation, and (c) data query tools. These tools work interoperably to standardize the entire process of annotation. The National Mesothelioma Virtual Bank tool is based upon the caTISSUE Clinical Annotation Engine, developed by the University of Pittsburgh in cooperation with the Cancer Biomedical Informatics Grid™ (caBIG™, see ). This application provides a web-based system for annotating, importing and searching mesothelioma cases. The underlying information model is constructed utilizing Unified Modeling Language class diagrams, hierarchical relationships and Enterprise Architect software.
Result
The database provides researchers real-time access to richly annotated specimens and integral information related to mesothelioma. The data disclosed is tightly regulated depending upon users' authorization and depending on the participating institute that is amenable to the local Institutional Review Board and regulation committee reviews.
Conclusion
The National Mesothelioma Virtual Bank currently has over 600 annotated cases available for researchers that include paraffin embedded tissues, tissue microarrays, serum and genomic DNA. The National Mesothelioma Virtual Bank is a virtual biospecimen registry with robust translational biomedical informatics support to facilitate basic science, clinical, and translational research. Furthermore, it protects patient privacy by disclosing only de-identified datasets to assure that biospecimens can be made accessible to researchers.
doi:10.1186/1471-2407-8-236
PMCID: PMC2533341  PMID: 18700971
17.  Comparison Between Emergency Department and Inpatient Nurses’ Perceptions of Boarding of Admitted Patients 
Introduction:
The boarding of admitted patients in the emergency department (ED) is a major cause of crowding and access block. One solution is boarding admitted patients in inpatient ward (W) hallways. This study queried and compared ED and W nurses’ opinions toward ED and W boarding. It also assessed their preferred boarding location if they were patients.
Methods:
A survey administered to a convenience sample of ED and W nurses was performed in a 631-bed academic medical center (30,000 admissions/year) with a 68-bed ED (70,000 visits/ year). We identified nurses as ED or W, and if W, whether they had previously worked in the ED. The nurses were asked if there were any circumstances where admitted patients should be boarded in ED or W hallways. They were also asked their preferred location if they were admitted as a patient. Six clinical scenarios were then presented, and the nurses’ opinions on boarding based on each scenario were queried.
Results:
Ninety nurses completed the survey, with a response rate of 60%; 35 (39%) were current ED nurses (cED), 40 (44%) had previously worked in the ED (pED). For all nurses surveyed 46 (52%) believed admitted patients should board in the ED. Overall, 52 (58%) were opposed to W boarding, with 20% of cED versus 83% of current W (cW) nurses (P < 0.0001), and 28% of pED versus 85% of nurses never having worked in the ED (nED) were opposed (P < 0.001). If admitted as patients themselves, 43 (54%) of all nurses preferred W boarding, with 82% of cED versus 33% of cW nurses (P < 0.0001) and 74% of pED versus 34% nED nurses (P = 0.0007). The most commonly cited reasons for opposition to hallway boarding were lack of monitoring and patient privacy. For the 6 clinical scenarios, significant differences in opinion regarding W boarding existed in all but 2 cases: a patient with stable chronic obstructive pulmonary disease but requiring oxygen, and an intubated, unstable sepsis patient.
Conclusion:
Inpatient nurses and those who have never worked in the ED are more opposed to inpatient boarding than ED nurses and nurses who have worked previously in the ED. Primary nursing concerns about boarding are lack of monitoring and privacy in hallway beds. Nurses admitted as patients seemed to prefer not being boarded where they work. ED and inpatient nurses seemed to agree that unstable or potentially unstable patients should remain in the ED but disagreed on where more stable patients should board.
doi:10.5811/westjem.2012.12.12830
PMCID: PMC3628487  PMID: 23599839
18.  Radon and monocytic leukaemia in England. 
The relationship between the standardised registration ratio (SRR) for monocytic leukaemia and the radon concentration by county in England was investigated. Leukaemia data were obtained from the OPCS and cover the age range 0-74 years and the period 1975-86. Radon concentrations were obtained from a recent National Radiological Protection Board report. A significant correlation was observed between the SRR for monocytic leukaemia and the radon concentration by county.
PMCID: PMC1059868  PMID: 8120509
19.  Radiation-induced chromosome damage in human lymphocytes 
ABSTRACT Analysis for chromosome aberrations in human peripheral blood lymphocytes has been developed as an indicator of dose from ionising radiation. This paper outlines the mechanism of production of aberrations, the technique for their analysis and the dose-effect relationships for various types of radiation. During the past ten years the National Radiological Protection Board has developed a service for the UK in which estimates of dose from chromosome aberration analysis are made on people known or suspected of being accidentally over-exposed. This service can provide estimates where no physical dosemeter was worn and is frequently able to resolve anomalous or disputed data from routine film badges. Several problems in the interpretation of chromosome aberration yields are reviewed. These include the effects of partial body irradiation and the response to variations in dose rate and the intermittent nature of some exposures. The dosimetry service is supported by a research programme which includes surveys of groups of patients irradiated for medical purposes. Two surveys are described. In the first, lymphocyte aberrations were examined in rheumatiod arthritis patients receiving intra-articular injections of colloidal radiogold or radioyttrium. A proportion of the nuclide leaked from the joint into the regional lymphatic system. In the second survey a comparison was made between the cytogenetic and physical estimates of whole body dose in patients receiving iodine 131 for thyroid carcinoma.
Images
PMCID: PMC1008276  PMID: 338021
20.  FSWs Typology and Condoms Use Among HIV High Risk Groups in Sindh, Pakistan: A Developing Country Perspective 
Objective
We aimed to determine the association of FSWs typology with condom use among HIV high risk groups in Sindh, Pakistan
Introduction
HIV is growing rapidly worldwide resulting in estimated 34 million population [1]. Recently, its epidemic has spread in Africa, Latin America, and the Caribbean, and most parts of Asia [2]. According to Antenatal sero surveillance study conducted in 2011 by Agriteam canada, it’s prevalence in Pakistan is <0.1 [3].Focusing narrowly, its prevalence in Sindh, (one of the provinces of Pakistan) is similar in general population, but it is in the phase of concentrated epidemic (having more than 5% of prevalence in high risk groups)in vulnerable groups like IDUs and Male sex workers and transgender [4].
Sexual intercourse has been identified as major route especially in HIV high risk groups including male sex workers, female sex workers (FSWs), transgender (hijras) and IV drug users. Among them, FSWs are at high risk because of unprotected sex and illicit drug use. Their prevalence is found to be 30.7% in low and middle income countries [5]. South Asia contributed with 12.63 lakh FSW in India only [6]. On the basis of their station of work, they are categorized into facility based (kothikhana, brothel or home) and mobile (street, mobile or beggars). They use different preventive measures including condom for their protection from HIV [7]. It varies with availability and access [8] . FSWs typology have different cliental and mode of action, therefore, it important to explore the preventive methods.
Methods
Data was extracted from Second Generation Surveillance, Integrated behavioral and biological survey, Round IV for HIV infection conducted by Agriteam Canada in partnership with National AIDS Control Program, Pakistan in 2011. It was a cross sectional survey for high risk groups including FSWs from Pakistan. It was ethically approved by Review Board of the Public Health Agency of Canada and HOPE International’s Ethical Review Board, Pakistan. From Sindh province, FSWs based in Karachi, Sukkur and Larkana were recruited. Considering typology, they were categorized as mobile or facility based. After informed consent, socio-demographic and risk behavior were inquired. HIV was tested by ELISA/EIA and confirmed by Western Blot. Data was analyzed on SPSS 19. Continuous variables were expressed as mean±SD while categorical as frequency(%). Logistic regression assessed the association of FSWs typology with condoms use among HIV high risk groups.
Results
Out of 4567 high risk population, 1127 were identified as FSWs. Mean age was 26.9 years. Most of them were facility based (72.8%) and 81.3% used condoms. Typology, age, education, duration of involvement, number of client per day, number of paid oral sex per month, knowledge about STI and knowledge about drop in center were significantly associated with condom use among HIV high risk groups.
Conclusions
Majority of facility based FSWs use condoms to prevent HIV infection. Awareness and access to home based FSWs should be increased. It may help in targeting and designing preventive strategies for them at government and mass level.
PMCID: PMC3692789
FSW; typology; condoms; HIV high risk groups; Pakistan
21.  Variation in recruitment across sites in a consent-based clinical data registry: lessons from the Canadian Stroke Network 
BMC Medical Ethics  2006;7:6.
Background
In earlier work, we found important selection biases when we tried to obtain consent for participation in a national stroke registry. Recognizing that not all registries will be exempt from requiring consent for participation, we examine here in greater depth the reasons for the poor accrual of patients from a systems perspective with a view to obtaining as representative sample as possible.
Methods
We determined the percent of eligible patients who were approached to participate and, among those approached, the percent who actually consented to participate. In addition we examined the reasons why people were not approached or did not consent and the variation across sites in the percent of patients approached and consented. We also considered site variation in restrictions on the accrual and data collection process imposed by either the local research ethics board or the hospital.
Results
Seventy percent of stroke patients were approached, with wide variations in approach rates across sites (from: 41% to 86%), and considerable inter-site variation in hospital policies governing patient accrual. Chief reasons for not approaching were discharge or death before being approached for consent. Seventeen percent of those approached refused to participate (range: 5% to 75%). Finally, 11% of those approached did not participate due to language or communication difficulties.
Conclusion
We found wide variation in approach and agree rates across sites that were accounted for, in part, by different approaches to accrual and idiosyncratic policies of the hospitals. This wide variation in approach and agree rates raises important challenges for research ethics boards and data protection authorities in determining when to waive consent requirements, when to press for increased quality control, when to permit local adaptation of the consent process, and when to permit alternatives to individual express consent. We offer several suggestions for those registries that require consent for participation.
doi:10.1186/1472-6939-7-6
PMCID: PMC1513239  PMID: 16716233
22.  ORGAN-SPECIFIC EXTERNAL DOSE COEFFICIENTS AND PROTECTIVE APRON TRANSMISSION FACTORS FOR HISTORICAL DOSE RECONSTRUCTION FOR MEDICAL PERSONNEL 
Health physics  2011;101(1):13-27.
While radiation absorbed dose (Gy) to the skin or other organs is sometimes estimated for patients from diagnostic radiologic examinations or therapeutic procedures, rarely is occupationally-received radiation absorbed dose to individual organs/tissues estimated for medical personnel, e.g., radiologic technologists or radiologists. Generally, for medical personnel, equivalent or effective radiation doses are estimated for compliance purposes. In the very few cases when organ doses to medical personnel are reconstructed, the data is usually for the purpose of epidemiologic studies, e.g., a study of historical doses and risks to a cohort of about 110,000 radiologic technologists presently underway at the U.S. National Cancer Institute. While ICRP and ICRU have published organ-specific external dose conversion coefficients (DCCs), i.e., absorbed dose to organs and tissues per unit air kerma and dose equivalent per unit air kerma, those factors have been primarily published for mono-energetic photons at selected energies. This presents two related problems for historical dose reconstruction, both of which are addressed here. It is necessary to derive conversion factors values for (i) continuous distributions of energy typical of diagnostic medical x rays (bremsstrahlung radiation), and (ii) for energies of particular radioisotopes used in medical procedures, neither of which are presented in published tables. For derivation of DCCs for bremsstrahlung radiation, combinations of x-ray tube potentials and filtrations were derived for different time periods based on a review of relevant literature. Three peak tube potentials (70 kV, 80 kV, and 90 kV) with four different amounts of beam filtration were determined to be applicable for historic dose reconstruction. The probability of these machine settings were assigned to each of the four time periods (earlier than 1949, 1949-1954, 1955-1968, and after 1968). Continuous functions were fit to each set of discrete values of the ICRP/ICRU mono-energetic DCCs and the functions integrated over the air-kerma weighted photon fluence of the 12 defined x-ray spectra. The air kerma-weighted DCCs in this work were developed specifically for an irradiation geometry of anterior to posterior (AP) and for the following tissues: thyroid, breast, ovary, lens of eye, lung, colon, testes, heart, skin (anterior side only), red bone marrow (RBM), heart, and brain. In addition, a series of functional relationships to predict DT per Ka values for RBM dependent on body mass index [BMI (kg m−2) ≡ weight per height2] and average photon energy were derived from a published analysis. Factors to account for attenuation of radiation by protective lead aprons were also developed. Because lead protective aprons often worn by radiology personnel not only reduce the intensity of x-ray exposure but also appreciably harden the transmitted fluence of bremsstrahlung x rays, DCCs were separately calculated for organs possibly protected by lead aprons by considering three cases: no apron, 0.25 mm Pb apron, and 0.5 mm Pb apron. For estimation of organ doses from conducting procedures with radioisotopes, continuous functions of the reported mono-energetic values were developed and DCCs were derived by estimation of the function at relevant energies. By considering the temporal changes in primary exposure-related parameters, e.g., energy distribution, the derived DCCs and transmission factors presented here allow for more realistic historical dose reconstructions for medical personnel when monitoring badge readings are the primary data on which estimation of an individual's organ doses are based.
doi:10.1097/HP.0b013e318204a60a
PMCID: PMC3964780  PMID: 21617389
23.  Fine Particulate Matter National Ambient Air Quality Standards: Public Health Impact on Populations in the Northeastern United States 
Environmental Health Perspectives  2005;113(9):1140-1147.
In this article we identify the magnitude of general and susceptible populations within the northeastern United States that would benefit from compliance with alternative U.S. Environmental Protection Agency (EPA) annual and 24-hr mass-based standards for particulate matter (PM) with an aerodynamic diameter ≤2.5 μm (PM2.5). Understanding the scale of susceptibility in relation to the stringency or protectiveness of PM standards is important to achieving the public health protection required by the Clean Air Act of 1970. Evaluative tools are therefore necessary to place into regulatory context available health and monitoring data appropriate to the current review of the PM National Ambient Air Quality Standards (NAAQS). Within the New England, New Jersey, and New York study area, 38% of the total population are < 18 or ≥65 years of age, 4–18% of adults have cardiopulmonary or diabetes health conditions, 12–15% of children have respiratory allergies or lifetime asthma, and 72% of all persons (across child, adult, and elderly age groups) live in densely populated urban areas with elevated PM2.5 concentrations likely creating heightened exposure scenarios. The analysis combined a number of data sets to show that compliance with a range of alternative annual and 24-hr PM2.5 standard groupings would affect a large fraction of the total population in the Northeast. This work finds that current PM2.5 standards in the eight-state study area affect only 16% of the general population, who live in counties that do not meet the existing annual/24-hr standard of 15/65 μg/m3. More protective PM2.5 standards recommended or enacted by California and Canada would protect 84–100% of the Northeast population. Standards falling within current ranges recommended by the U.S. EPA would protect 29–100% of the Northeast population. These considerations suggest that the size of general and susceptible populations affected by the stringency of alternative PM standards has broad implications for risk management and direct bearing on the U.S. EPA’s current NAAQS review and implementation.
doi:10.1289/ehp.7822
PMCID: PMC1280392  PMID: 16140618
air pollution; National Ambient Air Quality Standards; northeastern United States; particulate matter; PM2.5; populations; public health; sensitive; susceptible
24.  County Differences in Mortality among Foreign-Born Compared to Native Swedes 1970–1999 
Nursing Research and Practice  2012;2012:136581.
Background. Regional variations in mortality and morbidity have been shown in Europe and USA. Longitudinal studies have found increased mortality, dissimilarities in mortality pattern, and differences in utilization of healthcare between foreign- and native-born Swedes. No study has been found comparing mortality among foreign-born and native-born Swedes in relation to catchment areas/counties. Methods. The aim was to describe and compare mortality among foreign-born persons and native Swedes during 1970–1999 in 24 counties in Sweden. Data from the Statistics Sweden and the National Board of Health and Welfare was used, and the database consisted of 723,948 persons, 361,974 foreign-born living in Sweden in 1970 and aged 16 years and above and 361,974 matched Swedish controls. Results. Latest county of residence independently explained higher mortality among foreign-born persons in all but four counties; OR varied from 1.01 to 1.29. Counties with a more rural structure showed the highest differences between foreign-born persons and native controls. Foreign-born persons had a lower mean age (1.0–4.3 years) at time of death. Conclusion. County of residence influences mortality; higher mortality is indicated among migrants than native Swedes in counties with a more rural structure. Further studies are needed to explore possible explanations.
doi:10.1155/2012/136581
PMCID: PMC3458277  PMID: 23029609
25.  Utilization of In-Hospital Care among Foreign-Born Compared to Native Swedes 1987–1999 
Nursing Research and Practice  2012;2012:713249.
In previous longitudinal studies of mortality and morbidity among foreign-born and native-born Swedes, increased mortality and dissimilarities in mortality pattern were found. The aim of this study is to describe, compare, and analyse the utilization of in-hospital care among deceased foreign- and Swedish-born persons during the years 1987–1999 with focus on four diagnostic categories. The study population consisted of 361,974 foreign-born persons aged 16 years and upward who were registered as living in Sweden in 1970, together with 361,974 matched Swedish controls for each person. Data from Statistics Sweden (SCB) and the National Board of Health and Welfare Centre for Epidemiology, covering the period 1970–1999, was used. Persons were selected if they were admitted to hospital during 1987–1999 and the cause of death was in one of four ICD groups. The results indicate a tendency towards less health care utilization among migrants, especially men, as regards Symptoms, signs, and ill-defined conditions and Injury and poisoning. Further studies are needed to explore the possible explanations and the pattern of other diseases to see whether migrants, and especially migrant men, are a risk group with less utilization of health care.
doi:10.1155/2012/713249
PMCID: PMC3504430  PMID: 23213496

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