Concerns Regarding Results of a Randomized Controlled Trial to Promote Skin Self-Examination and Sun Protection Behaviors

Abstract

To the Editor We write regarding 2 articles by Aneja and colleagues1- 2 describing results of a randomized trial to promote skin self-examination (SSE) and sun-protection behaviors among individuals attending dermatology clinics. A key concern is that imbalance in baseline levels of each behavioral outcome (ie, performance of SSE, use of sun-protective clothing, and sunscreen use) may explain or attenuate treatment arm differences at follow-up. For example, use of sun-protective clothing at the follow-up was significantly higher among intervention than control group participants.2 However, 40.2% of intervention group participants reported always or frequently using sun-protective clothing at baseline compared with 28.6% of control group participants.1 A prudent approach should include sensitivity regression analyses (akin to those summarized in Table 31 and the Table2) estimating intervention effects on behavioral outcomes at the 3-month follow-up after controlling for the baseline levels. If baseline adjustments yielded nonsignificant results, then intervention effects would need to be interpreted with more caution.