Measuring exposure to solar ultraviolet radiation using a dosimetric technique: Understanding participant compliance issues

Personal ultraviolet dosimeters have been used in epidemiological studies to understand the risks and benefits of individuals' exposure to solar ultraviolet radiation (UVR). We investigated the types and determinants of noncompliance associated with a protocol for use of polysulphone UVR dosimeters. In the AusD Study, 1002 Australian adults (aged 18-75 years) were asked to wear a new dosimeter on their wrist each day for 10 consecutive days to quantify their daily exposure to solar UVR. Of the 10 020 dosimeters distributed, 296 (3%) were not returned or used (Type-I noncompliance) and other usage errors were reported for 763 (8%) returned dosimeters (Type-II noncompliance). Type-I errors were more common in participants with predominantly outdoor occupations. Type-II errors were reported more frequently on the first day of measurement; weekend days or rainy days; and among females; younger people; more educated participants or those with outdoor occupations. Half (50%) the participants reported a noncompliance error on at least 1 day during the 10-day period. However, 92% of participants had at least 7 days of usable data without any apparent noncompliance issues. The factors identified should be considered when designing future UVR dosimetry studies. Among 10 020 polysulphone UV dosimeters distributed in the AusD Study, the majority (89%) were returned with no reported issues, but 3% were not returned or used and 8% were returned with self-reported usage errors such as "missing some time," "covered by clothing," or "dosimeter got wet" that may potentially compromise the measurement quality. We found these noncompliance issues were more frequently reported on the first day of measurement; weekend days or rainy days; and among females; younger people; more educated participants or those with predominantly outdoor occupations. These factors should be considered when designing future UV dosimetry studies.