May, Anne MAdema, Lotte ERomaguera, DoraVergnaud, Anne-ClaireAgudo, AntonioEkelund, UlfSteffen, AnnikaOrfanos, PhilipposSlimani, NadiaRinaldi, SabinaMouw, TraciRohrmann, SabineHermann, SilkeBoeing, HeinerBergmann, Manuela MJakobsen, Marianne UhreOvervad, KimWareham, Nicholas JGonzalez, CarlosTjonneland, AnneHalkjaer, JytteKey, Timothy JSpencer, Elizabeth AHellstrom, VeronicaManjer, JonasHedblad, BoLund, EilivBraaten, TonjeClavel-Chapelon, FrançoiseBoutron-Ruault, Marie-ChristineRodríguez, LaudinaSanchez-Perez, Maria-JoseDorronsoro, MirenBarricarte, AurelioHuerta, Jose MariaNaska, AndronikiTrichopoulou, AntoniaPalli, DomenicoPala, ValeriaNorat, TeresaMattiello, AmaliaTumino, Rosariovan der A, DaphneBueno-de-Mesquita, H BasRiboli, ElioPeeters, Petra H M2013-02-192013-02-192012-09-24May AM, Adema LE, Romaguera D, Vergnaud AC, Agudo A, Ekelund U, et al. Determinants of non- response to a second assessment of lifestyle factors and body weight in the EPIC-PANACEA study. BMC Med Res Methodol 2012; 12:148http://hdl.handle.net/10668/777PubMed - in processBACKGROUND This paper discusses whether baseline demographic, socio-economic, health variables, length of follow-up and method of contacting the participants predict non-response to the invitation for a second assessment of lifestyle factors and body weight in the European multi-center EPIC-PANACEA study. METHODS Over 500.000 participants from several centers in ten European countries recruited between 1992 and 2000 were contacted 2-11 years later to update data on lifestyle and body weight. Length of follow-up as well as the method of approaching differed between the collaborating study centers. Non-responders were compared with responders using multivariate logistic regression analyses. RESULTS Overall response for the second assessment was high (81.6%). Compared to postal surveys, centers where the participants completed the questionnaire by phone attained a higher response. Response was also high in centers with a short follow-up period. Non-response was higher in participants who were male (odds ratio 1.09 (confidence interval 1.07; 1.11), aged under 40 years (1.96 (1.90; 2.02), living alone (1.40 (1.37; 1.43), less educated (1.35 (1.12; 1.19), of poorer health (1.33 (1.27; 1.39), reporting an unhealthy lifestyle and who had either a low (<18.5 kg/m2, 1.16 (1.09; 1.23)) or a high BMI (>25, 1.08 (1.06; 1.10); especially ≥30 kg/m2, 1.26 (1.23; 1.29)). CONCLUSIONS Cohort studies may enhance cohort maintenance by paying particular attention to the subgroups that are most unlikely to respond and by an active recruitment strategy using telephone interviews.enNon-responseNon-participationLost-to-follow-upFollow-upHealth surveyNonresponse biasSelection biasPopulationcohortAttritionrepresentativenessParticipationPredictorsEncuestas epidemiológicasEstilo de VidaMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Data Collection::Health SurveysMedical Subject Headings::Psychiatry and Psychology::Behavior and Behavior Mechanisms::Psychology, Social::Life Styleresearch article23006680open access10.1186/1471-2288-12-1481471-2288PMC3502143