Studies were identified for the review by a comprehensive search of three databases (MEDLINE, PsychINFO, CINAHL) for primary reports of interventions, published in English from 1966–2000, that compared outcomes among persons exposed to interventions with persons not exposed or less exposed to the interventions. A systematic review in which 6000+ titles and citations were screened; 159 articles reviewed; and 85 studies included in the skin cancer prevention review [14
]. Additional studies published after 2000 were included if they became available through a call for input to active skin cancer prevention researchers.
For the review in occupational settings, 14 reports that met the inclusion criteria were identified. Of those, there were 8 qualifying studies; 6 reports were excluded due to methodological limitations or because they were reporting on already-included studies. The types of workers who were the focus of the included studies included lifeguards [27
], outdoor recreation staff [28
], outdoor utility company workers [30
], and various outdoor workers [23
Following the standard Guide
], each study was evaluated using a standardized abstraction form and was assessed for suitability of study design and threats to validity. Two abstractors evaluated each study and the abstractions were reviewed, and reconciled when necessary, by a multidisciplinary team of scientists.
A conceptual model, or analytic framework, was developed to show the relationship of the interventions to relevant intermediate outcomes (e.g., knowledge, attitudes, intentions regarding sun-protective behaviors), and to behaviors and skin cancer prevention. Outcome data extracted from the studies were aligned with the analytic framework, to answer specific research questions. Key elements of the framework for the review of interventions in occupations settings were: the intervention; increases in employee knowledge, attitudes and intentions to reduce UV exposure or increase solar protection; changes in exposure and protection; reduction of sunburn; and changes in workplace policies and environments to reduce exposure (e.g., limiting exposure during midday, increasing shade, providing sunscreen, etc.). Although none of the studies identified measured decreased incidence of precancer, nevi, or photodamage; or decreased incidence of skin cancer; it was assumed by the review team that the behavioral changes and reduction of sunburn, if found, would lead to lower rates of cancer [14
Summary of community guide review
Results of the evidence review
Our search identified 8 qualifying reports (summarized in Table ) that evaluated the effectiveness of interventions to reduce UV exposure in worksites. The reports involved numerous intervention activities and evaluated a variety of outcomes. Most of the interventions used combinations of strategies, as shown in Table . Five reports consisted of interventions that provided sun-safety training to workers; and two. involved sun-protection and skin cancer education sessions and skin exams by a physician. Six studies promoted covering-up behaviors; five involved role-modeling by lifeguards or aquatics instructors; one provided sun protection to outdoor workers (sunglasses, brimmed hat, and sunscreen); one used educational brochures designed for men over the age of 45 and a body chart for self-assessment of pigmented lesions to educate male workers about skin cancer; and two. used environmental supports (sunscreen dispensers and shade structures) to promote sun-protective behavior.
Studies evaluating interventions to improve sun protection by outdoor workers
In the Results column of Table , we summarize the changes found in various study endpoints, and the percentage change for different outcomes. Eleven study arms from seven reports examined changes in sun-protective behaviors and UV exposure and one examined incidence of sunburn. Available reports provided insufficient evidence to determine effectiveness of the intervention in increasing the sun-protective behaviors of covering up. or seeking shade, or in decreasing the incidence of sunburn and UV exposure, because of the small number of reports and inconsistent results.
Six arms from five reports examined knowledge; five arms from four reports examined attitudes or beliefs; and three arms from two reports. examined environmental pool policies. Six arms from five reports demonstrated inconsistent effects on knowledge, and five arms from four reports demonstrated inconsistent effects on attitudes or beliefs. Three arms from two reports. examining sun-protection demonstrated desirable effects of the intervention on sun-safety measures and environmental supports (provision of sunscreen dispensers and portable shade structures) at recreational centers and swimming pools.
According to the Guide rules of evidence, available reports provide insufficient evidence to determine the effectiveness of interventions in occupational settings because of too few reports and inconsistent evidence.
Other issues examined in the Guide evidence review
In addition to examining the effectiveness of interventions to reduce UV exposure, the evidence review uses the current evidence base to assess whether conclusions can be drawn regarding several other issues: applicability; economic efficiency; barriers to implementation; and other positive or negative effects. In this review, evidence about applicability was not assessed for this intervention because effectiveness was not established. Also, economic evidence and evidence about barriers to implementation were not collected, either, because effectiveness was not established.
With regard to other positive or negative effects, reviewed studies did not include information on other potential effects of these interventions. Other positive effects may include reaching populations that might not otherwise be exposed to skin cancer prevention and reducing risk of overexposure to heat. Potential negative effects of interventions may include worker requests for reductions in time spent working outdoors and increased costs to employers that are passed on to consumers (e.g., taxpaying public, utility customers, swimming pool users, etc.).
Recently completed intervention research
Two large intervention studies to improve sun protection among outdoor workers were published since the community guide review was completed. They include a large study of ski area employees in North America [18
] and a study of mail carriers in Southern California [47
]. These studies help to strengthen the evidence base because both employed group-randomized pretest-posttest controlled trial designs, innovative interventions, and highly credible outcome measures; they have been included in Table to update the previous data. The study of ski area employees found a reduction in sunburns among intervention site employees [18
] and there was evidence of intervention effects on sun protection behaviors into summer months when the seasonal employees in this industry work elsewhere, many at other outdoor occupations [49
]. The study of postal workers found both short-term and persistent effects of the intervention on sunscreen use and wide-brim hat use [48
]. In addition, both these studies included systematic analyses of implementation and results showed that there were dose-response effects indicating that employees who were most-exposed to the interventions showed greater increases in sun-protection behaviors [18
Interpreting conclusions from the evidence review and important research and practice considerations
The available reports provide insufficient evidence to determine the effectiveness of interventions in occupational settings to reduce UV exposure and increase sun-protection behavior because of too few reports and inconsistent evidence. This does not, however, mean that the individual studies did not find positive effects; but rather, that there were too few well-designed studies to conclude that specific types of strategies are effective. These findings need to be considered in the context of the broader field of skin cancer prevention, and in view of what we understand from descriptive studies of outdoor workers' sun-safety knowledge, attitudes, and practices.
Indeed, we should bear in mind that this is a relatively young field with a small literature, and take these findings as the foundation upon which to build a body of evidence that informs occupational medicine and cancer prevention program design. Future studies should include randomized, often group-randomized designs; longer follow-up periods; multiple outcome measures including those that go beyond self-report to include observations and biological assessments on at least a sub-sample of participants; and vigorous attention to reduce attrition [50
]. The recently completed studies by Buller [18
] and Mayer [48
] illustrate several of these improved study features and are excellent models for continual improvement in this scientific area.
Research in progress
Two of the authors on the present manuscript are also investigating issues related to the dissemination of sun safety interventions in workplaces – i.e., how employers decide to adopt sun protection education programs and how well they implement them, outside of a highly controlled research trial. Specifically, Glanz and colleagues are examining the diffusion of the Pool Cool
sun safety program to swimming pools throughout the United States [50
] lifeguards and aquatic instructors are both targets of the intervention and intermediaries who serve as role models to children and other poolgoers. This study includes more than 5,000 lifeguards a year for three years. Buller is studying the dissemination of Go Sun Smart to ski areas in North America through the National Ski Areas Association and its membership. This study includes on-site observations at 69 ski areas and surveys with nearly 500 managers on adoption decisions and implementation actions.