Recalling our day in the sun: comparing long-term recall of childhood sun exposure with prospectively collected parent-reported data

To examine the impact of sun exposure on human health, accurate measures of past sun exposure are required. We investigated how young adults' recall of childhood sun-related behaviours compares with parent-reported measures collected during childhood. The Kidskin-Young Adult Myopia Study (KYAMS) is a follow-up of the Kidskin Study, a sun-protection intervention study conducted from 1995-2001. KYAMS participants, aged 25-30 years, reported time in sun, and use of hats and sunscreen, for each year from ages 5-26 years (n = 244). Using weighted kappa, we assessed agreement between these data and corresponding variables derived from the Kidskin Study parent questionnaires completed when KYAMS participants were aged 6-12 years. Ordinal logistic regression was used to test the association between self-reported sun-behaviours and corresponding parent-reported data. We found slight agreement between self-reported and parent-reported data for all sun-behaviour measures except hat use at 12 years. KYAMS recall of time in sun at 8-12 years was not associated with Kidskin Study parent-reported responses after adjustment for current time in sun. Recall of higher hat and sunscreen use was associated with higher parent-reported hat and sunscreen use (OR[hat] = 1.37, 95% CI: 1.16, 1.62; OR[sunscreen] = 1.23, 95% CI: 1.03, 1.48). However, KYAMS self-reported data were unable to predict corresponding parent-reported responses. Group data from retrospective recall of sun-related behaviours may be of limited value in studying the relationship between sun exposure and health outcomes; however, individual data are likely of little use.