The World Health Organization (WHO) has argued that functioning, and, more concretely, functioning domains constitute the operationalization that best captures our intuitive notion of health. Functioning is, therefore, a major public-health goal. A great deal of data about functioning is already available. Nonetheless, it is not possible to compare and optimally utilize this information. One potential approach to address this challenge is to propose a generic and minimal set of functioning domains that captures the experience of individuals and populations with respect to functioning and health. The objective of this investigation was to identify a minimal generic set of ICF domains suitable for describing functioning in adults at both the individual and population levels.
We performed a psychometric study using data from: 1) the German National Health Interview and Examination Survey 1998, 2) the United States National Health and Nutrition Examination Survey 2007/2008, and 3) the ICF Core Set studies. Random Forests and Group Lasso regression were applied using one self-reported general-health question as a dependent variable. The domains selected were compared to those of the World Health Survey (WHS) developed by the WHO.
Seven domains of the International Classification of Functioning, Disability and Health (ICF) are proposed as a minimal generic set of functioning and health: energy and drive functions, emotional functions, sensation of pain, carrying out daily routine, walking, moving around, and remunerative employment. The WHS domains of self-care, cognition, interpersonal activities, and vision were not included in our selection.
The minimal generic set proposed in this study is the starting point to address one of the most important challenges in health measurement – the comparability of data across studies and countries. It also represents the first step in developing a common metric of health to link information from the general population to information about sub-populations, such as clinical and institutionalized populations.
ICF; Functioning; Health; Data comparability
Lived health is a person’s level of functioning in his or her current environment and depends both on the person’s environment and biological health. Our study addresses the question whether biological health or lived health is more predictive of self-reported general health (SRGH).
This is a psychometric study using cross-sectional data from the Spanish Survey on Disability, Independence and Dependency Situation. Data was collected from 17,739 people in the community and 9,707 from an institutionalized population. The following analysis steps were performed: (1) a biological health and a lived health score were calculated for each person by constructing a biological health scale and a lived health scale using Samejima’s Graded Response Model; and (2) variable importance measures were calculated for each study population using Random Forest, with SRGH as the dependent variable and the biological health and the lived health scores as independent variables.
The levels of biological health were higher for the community-dwelling population than for the institutionalized population. When technical assistance, personal assistance or both were received, the difference in lived health between the community-dwelling population and institutionalized population was smaller. According to Random Forest’s variable importance measures, for both study populations, lived health is a more important predictor of SRGH than biological health.
In general, people base their evaluation of their own health on their lived health experience rather than their experience of biological health. This study also sheds light on the challenges of assessing biological health and lived health at the general population level.
Self-reported general health; Biological health; Lived health; Graded Response Model; Random Forest; Spain
To understand the full burden of a health condition, we need the information on the disease and the information on how that disease impacts the functioning of an individual. The ongoing revision of the International Classification of Diseases (ICD) provides an opportunity to integrate functioning information through the International Classification of Functioning, Disability and Health (ICF).
Part of the ICD revision process includes adding information from the ICF by way of “functioning properties” to capture the impact of the disease on functioning. The ICD content model was developed to provide the structure of information required for each ICD-11 disease entity and one component of this content model is functioning properties. The activities and participation domains from ICF are to be included as the value set for functioning properties in the ICD revision process.
The joint use of ICD and ICF could create an integrated health information system that would benefit the implementation of a standard language-based electronic health record to better capture and understand disease and functioning in healthcare.
International classification of diseases; ICF; Classification; Functioning; ICD revision; Disability
The “Comprehensive ICF Core Set for Chronic Obstructive Pulmonary Diseases (COPD)“ is an application of the International Classification of Functioning, Disability and Health (ICF) and represents the typical spectrum of problems in functioning of patients with COPD. The objective of this study was to validate this ICF Core Set from the perspective of physicians.
Materials and Methodology:
Physicians experienced in COPD treatment were asked about the patients’ problems treated by physicians in patients with COPD in a three-round electronic mail survey using the Delphi technique. Responses were linked to the ICF.
Seventy-six physicians in 44 countries gave a total of 1330 responses that were linked to 148 different ICF categories. Nine ICF categories were not represented in the Comprehensive ICF Core Set for COPD although at least 75% of the participants have rated them as important. Nineteen concepts were linked to the not yet developed ICF component personal factors and seventeen concepts were not covered by the ICF.
The high percentage of ICF categories represented in the ICF Core Set for COPD indicates satisfactory content validity from the perspective of the physicians. However, some issues were raised that were not covered and need to be investigated further.
Chronic obstructive pulmonary disease; asthma; rehabilitation; international classification of functioning; disability and health; ICF core set.
Medical work capacity evaluations play a key role in social security schemes because they usually form the basis for eligibility decisions regarding disability benefits. However, the evaluations are often poorly standardized and lack transparency as decisions on work capacity are based on a claimant’s disease rather than on his or her functional capacity. A comprehensive and consistent illustration of a claimant’s lived experience in relation to functioning, applying the International Classification of Functioning, Disability and Health (ICF) and the ICF Core Sets (ICF-CS), potentially enhances transparency and standardization of work capacity evaluations. In our study we wanted to establish whether and how the relevant content of work capacity evaluations can be captured by ICF-CS, using disability claimants with chronic widespread pain (CWP) and low back pain (LBP) as examples.
Mixed methods study, involving a qualitative and quantitative content analysis of medical reports. The ICF was used for data coding. The coded categories were ranked according to the percentage of reports in which they were addressed. Relevance thresholds at 25% and 50% were applied. To determine the extent to which the categories above the thresholds are represented by applicable ICF-CS or combinations thereof, measures of the ICF-CS’ degree of coverage (i.e. content validity) and efficiency (i.e. practicability) were defined.
Focusing on the 25% threshold and combining the Brief ICF-CS for CWP, LBP and depression for CWP reports, the coverage ratio reached 49% and the efficiency ratio 70%. Combining the Brief ICF-CS for LBP, CWP and obesity for LBP reports led to a coverage of 47% and an efficiency of 78%.
The relevant content of work capacity evaluations involving CWP and LBP can be represented by a combination of applicable ICF-CS. A suitable standard for documenting such evaluations could consist of the Brief ICF-CS for CWP, LBP, and depression or obesity, augmented by additional ICF categories relevant for this particular context. In addition, the unique individual experiences of claimants have to be considered in order to assess work capacity comprehensively.
International Classification of Functioning; Disability and Health (ICF); Work capacity evaluation; Chronic widespread pain; Low back pain; Standardization
Disability can be broken down into difficulties in different components of functioning such as impairments and limitations in activities and participation (A&P). Previous studies have produced the seemingly surprising result that persons with severe impairments tend to report high quality of life (QoL) including perceived health regardless of their condition; the so-called “disability paradox”. We aim to study the role of contextual factors (i.e. the personal and environmental situation) in explaining the disability paradox.
The Swiss Health Survey provides information on the perceived health of 18,760 participants from the general population. We construct a conditional independence graph applying random forests and stability selection in order to represent the structure of impairment, A&P limitation, contextual factors, and perceived health.
We find that impairment and A&P limitations are not directly related but only via a cluster of contextual factors. Similarly, impairment and perceived health are not directly related. On the other hand, perceived health is directly connected with A&P limitations. We hypothesize that contextual factors have a moderating and/or mediating effect on the relationship of impairment, A&P limitations, and perceived health.
The disability paradox seems to dissolve when contextual factors are put into consideration. Contextual factors may be responsible for some persons with impairments developing A&P limitations and others not. In turn, persons with impairments may only then perceive bad health when they experience A&P limitation. Political interventions at the level of the environment may reduce the number of persons who perceive bad health.
Disability; Human functioning; Perceived health; Impairment; ICF; Graphical models; Activity limitation; Participation restriction
To study the relationship of waist circumference (WC) and bioelectrical impedance analysis (BIA) and degree of agreement between anthropometric index (AI) and BIA, using BIA as a reference or ‘gold standard’. The second objective is to study the relationship between body mass index (BMI) and BIA in subjects with spinal cord injury (SCI).
Comparative cross-sectional study.
Convenience sample at outpatient clinic of spinal cord center.
Estimation of obesity was made in 23 men with motor complete paraplegia (>1 year post-injury). Bland and Altman statistics were used to define level of agreement between AI and BIA, Pearson's r to describe correlation between WC and BIA and BMI and BIA.
Good agreement between BIA and AI with a small systematic difference in fat mass (FM) (mean difference: −0.28%, Pearson's r: 0.91) was found. The correlation between WC and the BIA (% FM) was very high (Pearson's r: 0.83). The correlation between WC and BMI (% FM) was just over moderate (Pearson's r: 0.51).
AI seems to be a valid proxy measure to estimate obesity in males living with SCI. Measurement of obesity in persons with SCI based on WC is promising. BMI showed not to be valid to estimate obesity in persons with SCI.
Spinal cord injuries; Obesity; Anthropometrics; Body mass index; Bioelectrical impedance analysis
The impact of inflammatory bowel disease (IBD) on disability remains poorly understood. The World Health Organization's integrative model of human functioning and disability in the International Classification of Functioning, Disability and Health (ICF) makes disability assessment possible. The ICF is a hierarchical coding system with four levels of details that includes over 1400 categories. The aim of this study was to develop the first disability index for IBD by selecting most relevant ICF categories that are affected by IBD.
Relevant ICF categories were identified through four preparatory studies (systematic literature review, qualitative study, expert survey and cross-sectional study), which were presented at a consensus conference. Based on the identified ICF categories, a questionnaire to be filled in by clinicians, called the ‘IBD disability index’, was developed.
The four preparatory studies identified 138 second-level categories: 75 for systematic literature review (153 studies), 38 for qualitative studies (six focus groups; 27 patients), 108 for expert survey (125 experts; 37 countries; seven occupations) and 98 for cross-sectional study (192 patients; three centres). The consensus conference (20 experts; 17 countries) led to the selection of 19 ICF core set categories that were used to develop the IBD disability index: seven on body functions, two on body structures, five on activities and participation and five on environmental factors.
The IBD disability index is now available. It will be used in studies to evaluate the long-term effect of IBD on patient functional status and will serve as a new endpoint in disease-modification trials.
Antibacterial peptide; azathioprine; bacterial translocation; Crohn's colitis; Crohn's disease; disability; gut immunology; IBD basic research; IBD clinical; IBD models; ICF; immunology; inflammatory bowel disease; infliximab; lamina proprial lymphocytes; mucosal immunology; 6-mercaptopurine; thiopurine methyltransferase; ulcerative colitis
The comprehensive ICF Core Set for rheumatoid arthritis (RA) is a selection of 96 categories from the International Classification of Functioning, Disability and Health (ICF), representing relevant aspects in the functioning of RA patients.
To study the reliability of the ICF Core Set for RA in rheumatological practice, and to explore the metric of the qualifiers' scale.
25 RA patients from an outpatient department of rheumatology were interviewed using the ICF Core Set for RA (76% females, mean (SD) age 57.5 (12.5) years, disease duration 15.9 (14.6) years). Interviews were performed independently by both a physiotherapist and an occupational therapist on the same day and again after one week by one of them. The severity of the patients' problems was quantified on a qualifier scale ranging from 0 (no problem) to 4 (complete problem). Analyses of intra‐rater and inter‐rater agreement, kappa statistics, and Rasch analyses were applied.
Mean intra‐rater (inter‐rater) complete agreement for all categories was seen in 59% (47%) of observations, ranging from 29% (0%) to 96% (80%) for individual categories. Weighted kappa statistics with value ⩾0.4 showed reliability in 86% of categories within raters, and in 43% of categories between raters. Improved inter‐rater and intra‐rater reliability was observed with a reduced number of qualifiers for the categories.
Inter‐rater and intra‐rater reliability of the ICF Core Set of RA was low to moderate. The metric of the qualifiers' scale may be improved by reducing the number of qualifiers to three for all components.
International Classification of Functioning, Disability and Health (ICF); reliability; ICF Core Set; rheumatoid arthritis; health status measure
Functioning and disability are universal human experiences. However, our current understanding of functioning from a comprehensive perspective is limited. The development of the International Classification of Functioning, Disability and Health (ICF) on the one hand and recent developments in graphical modeling on the other hand might be combined and open the door to a more comprehensive understanding of human functioning. The objective of our paper therefore is to explore how graphical models can be used in the study of ICF data for a range of applications.
We show the applicability of graphical models on ICF data for different tasks: Visualization of the dependence structure of the data set, dimension reduction and comparison of subpopulations. Moreover, we further developed and applied recent findings in causal inference using graphical models to estimate bounds on intervention effects in an observational study with many variables and without knowing the underlying causal structure.
In each field, graphical models could be applied giving results of high face-validity. In particular, graphical models could be used for visualization of functioning in patients with spinal cord injury. The resulting graph consisted of several connected components which can be used for dimension reduction. Moreover, we found that the differences in the dependence structures between subpopulations were relevant and could be systematically analyzed using graphical models. Finally, when estimating bounds on causal effects of ICF categories on general health perceptions among patients with chronic health conditions, we found that the five ICF categories that showed the strongest effect were plausible.
Graphical Models are a flexible tool and lend themselves for a wide range of applications. In particular, studies involving ICF data seem to be suited for analysis using graphical models.
Functioning is recognized as an important study outcome in chronic widespread pain (CWP). The Comprehensive ICF Core Set for CWP is an application of the International Classification of Functioning, Disability and Health (ICF) with the purpose of representing the typical spectrum of functioning of patients with CWP. The objective of the study was to add evidence to the validation of the Comprehensive ICF Core Set for CWP from the patient perspective. The specific aims were to explore the aspects of functioning and health important to patients with fibromyalgia, and to examine to what extent these aspects are represented by the current version of the Comprehensive ICF Core Set for CWP.
The sampling of patients followed the maximum variation strategy. Sample size was determined by saturation. The focus groups were digitally recorded and transcribed verbatim. The meaning condensation procedure was used for qualitative data analysis. After qualitative data analysis, the identified concepts were linked to ICF categories.
Thirty-three patients participated in six focus groups. Fifty-four ICF categories out of 67 categories of the Comprehensive ICF Core Set for CWP were reported by the patients. Forty-eight additional categories that are not covered in the Comprehensive ICF Core Set for CWP were raised.
Most ICF categories of the existing version of the Comprehensive ICF Core Set for CWP could be confirmed from the patient perspective. However, several categories not included in the Core Set emerged and should be considered for inclusion.
The recovery of patients after an acute episode of illness or injury depends both on adequate medical treatment and on the early identification of needs for rehabilitation care. The process of early beginning rehabilitation requires efficient communication both between health professionals and the patient in order to effectively address all rehabilitation goals. The currently used nursing taxonomies, however, are not intended for interdisciplinary use and thus may not contribute to efficient rehabilitation management and an optimal patient outcome. The ICF might be the missing link in this communication process. The objective of this study was to identify the categories of the International Classification of Functioning, Disability and Health (ICF) categories relevant for nursing care in the situation of acute and early post-acute rehabilitation.
First, in a consensus process, "Leistungserfassung in der Pflege" (LEP) nursing interventions relevant for the situation of acute and early post-acute rehabilitation were selected. Second, in an integrated two-step linking process, two nursing experts derived goals of LEP nursing interventions from their practical knowledge and selected corresponding ICF categories most relevant for patients in acute and post-acute rehabilitation (ICF Core Sets).
Eighty-seven percent of ICF Core Set categories could be linked to goals of at least one nursing intervention variable of LEP. The ICF categories most frequently linked with LEP nursing interventions were respiration functions, experience of self and time functions and focusing attention. Thirteen percent of ICF Core Set categories could not be linked with LEP nursing interventions. The LEP nursing interventions which were linked with the highest number of different ICF-categories of all were "therapeutic intervention", "patient-nurse communication/information giving" and "mobilising".
The ICF Core Sets for the acute hospital and early post-acute rehabilitation facilities are highly relevant for rehabilitation nursing. Linking nursing interventions with ICF Core Set categories is a feasible way to analyse nursing. Using the ICF Core Sets to describe goals of nursing interventions both facilitates inter-professional communication and respects patient's needs. The ICF may thus be a useful framework to set nursing intervention goals.
The International Classification of Functioning, Disability and Health (ICF) is the framework developed by WHO to describe functioning and disability at both the individual and population levels.
While condition-specific ICF Core Sets are useful, a Generic ICF Core Set is needed to describe and compare problems in functioning across health conditions.
The aims of the multi-centre, cross-sectional study presented here were: a) to propose a method to select ICF categories when a large amount of ICF-based data have to be handled, and b) to identify candidate ICF categories for a Generic ICF Core Set by examining their explanatory power in relation to item one of the SF-36.
The data were collected from 1039 patients using the ICF checklist, the SF-36 and a Comorbidity Questionnaire.
ICF categories to be entered in an initial regression model were selected following systematic steps in accordance with the ICF structure. Based on an initial regression model, additional models were designed by systematically substituting the ICF categories included in it with ICF categories with which they were highly correlated.
Fourteen different regression models were performed. The variance the performed models account for ranged from 22.27% to 24.0%. The ICF category that explained the highest amount of variance in all the models was sensation of pain. In total, thirteen candidate ICF categories for a Generic ICF Core Set were proposed.
The selection strategy based on the ICF structure and the examination of the best possible alternative models does not provide a final answer about which ICF categories must be considered, but leads to a selection of suitable candidates which needs further consideration and comparison with the results of other selection strategies in developing a Generic ICF Core Set.
Functioning is recognized as an important study outcome in rheumatoid arthritis (RA). The Comprehensive ICF Core Set for RA is an application of the International Classification of Functioning, Disability and Health (ICF) of the World Health Organisation with the purpose of representing the typical spectrum of functioning of patients with RA. To strengthen the patient perspective, persons with RA were explicitly involved in the validation of the Comprehensive ICF Core Set for RA using qualitative methodology. The objective of the study was twofold: to come forward with a proposal for the most appropriate methodology to validate Comprehensive ICF Core Sets from the patient perspective; and to add evidence to the validation of the Comprehensive ICF Core Set for RA from the perspective of patients. The specific aims were to explore the aspects of functioning and health important to patients with RA using two different focus group approaches (open approach and ICF-based approach) and to examine to what extent these aspects are represented by the current version of the Comprehensive ICF Core Set for RA. The sampling of patients followed the maximum variation strategy. Sample size was determined by saturation. The focus groups were digitally recorded and transcribed verbatim. The meaning condensation procedure was used for the data analysis. After qualitative data analysis, the resulting concepts were linked to ICF categories according to established linking rules. Forty-nine patients participated in ten focus groups (five in each approach). Of the 76 ICF categories contained in the Comprehensive ICF Core Set for RA, 65 were reported by the patients based on the open approach and 71 based on the ICF-based approach. Sixty-six additional categories (open approach, 41; ICF-based approach, 57) that are not covered in the Comprehensive ICF Core Set for RA were raised. The existing version of the Comprehensive ICF Core Set for RA could be confirmed almost entirely by the two different focus group approaches applied. Focus groups are a highly useful qualitative method to validate the Comprehensive ICF Core Set for RA from the patient perspective. The ICF-based approach seems to be the most appropriate technique.