Yu Chu-Ling, Li Yan, Freedman D Michal, Fears Thomas R, Kwok Richard, Chodick Gabriel, Alexander Bruce, Kimlin Michael G, Kricker Anne, Armstrong Bruce K, Linet Martha S
Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Rockville, MD 20892-7238, USA.
Cancer Epidemiol Biomarkers Prev. 2009 Feb;18(2):464-71. doi: 10.1158/1055-9965.EPI-08-0894. Epub 2009 Feb 3.
Few studies have evaluated the reliability of lifetime sun exposure estimated from inquiring about the number of hours people spent outdoors in a given period on a typical weekday or weekend day (the time-based approach). Some investigations have suggested that women have a particularly difficult task in estimating time outdoors in adulthood due to their family and occupational roles. We hypothesized that people might gain additional memory cues and estimate lifetime hours spent outdoors more reliably if asked about time spent outdoors according to specific activities (an activity-based approach). Using self-administered, mailed questionnaires, test-retest responses to time-based and to activity-based approaches were evaluated in 124 volunteer radiologic technologist participants from the United States: 64 females and 60 males 48 to 80 years of age. Intraclass correlation coefficients (ICC) were used to evaluate the test-retest reliability of average number of hours spent outdoors in the summer estimated for each approach. We tested the differences between the two ICCs, corresponding to each approach, using a t test with the variance of the difference estimated by the jackknife method. During childhood and adolescence, the two approaches gave similar ICCs for average numbers of hours spent outdoors in the summer. By contrast, compared with the time-based approach, the activity-based approach showed significantly higher ICCs during adult ages (0.69 versus 0.43, P = 0.003) and over the lifetime (0.69 versus 0.52, P = 0.05); the higher ICCs for the activity-based questionnaire were primarily derived from the results for females. Research is needed to further improve the activity-based questionnaire approach for long-term sun exposure assessment.
很少有研究评估通过询问人们在典型工作日或周末的特定时间段内户外停留时间（基于时间的方法）来估算终生日照量的可靠性。一些调查表明，由于家庭和职业角色的原因，女性在估算成年后的户外时间方面面临特别困难的任务。我们假设，如果根据特定活动询问户外时间（基于活动的方法），人们可能会获得更多的记忆线索，并更可靠地估算终生户外停留时间。我们使用自行填写并邮寄的问卷，对来自美国的124名志愿者放射技师参与者（64名女性和60名男性，年龄在48至80岁之间）针对基于时间的方法和基于活动的方法进行了重测反应评估。组内相关系数（ICC）用于评估每种方法估算的夏季户外平均停留小时数的重测可靠性。我们使用t检验来检验两种方法对应的ICC之间的差异，差异方差采用刀切法估计。在童年和青少年时期，两种方法估算的夏季户外平均停留小时数的ICC相似。相比之下，与基于时间的方法相比，基于活动的方法在成年期（0.69对0.43，P = 0.003）和终生（0.69对0.52，P = 0.05）显示出显著更高的ICC；基于活动的问卷的较高ICC主要来自女性的结果。需要进一步研究以改进基于活动的问卷方法用于长期日照评估。
