Background: Following cessation interventions, self-reported smoking abstinence with biochemical verification is the "gold standard" for defining outcomes. Because obtaining biochemical verification is challenging in community studies, we compared self-reported cessation among smokers completing treatment to the smoking status reported by each participant's spouse or proxy.
Method: Participants were smokers who had reported quitting 12 months after a cessation intervention. Participants had either attended a smoking cessation clinic or they were patients seen by physicians who had recently participated in a cessation-training program. Proxies living with these participants were interviewed by telephone to ask about their partner's smoking status. We compared the participants' responses to those from their spouses.
Results: At 12 months, 346 of 1423 baseline smokers had quit; 161/346 reported non-smokers were called and 140 proxies were interviewed. The participants averaged 51 years of age, 69% were women. At baseline, the mean number of cigarettes smoked per day was 20.1 (SD = 9.9) and the average number of quit attempts was 2.4 (SD = 1.2). Cessation methods used were medical advice (21%) and/or pharmacotherapy (79%). Of the 140 spouses interviewed, only 10 (7.1%) reported that their partners were currently smoking.
Conclusions: Proxy-reported data on smoking status could be used to validate self-report.