Who does not participate in a follow-up postal study? a survey of infertile couples treated by in vitro fertilization

Abstract

BackgroundA good response rate has been considered as a proof of a study’s quality. Decreasing participation and its potential impact on the internal validity of the study are of growing interest. Our objective was to assess factors associated with contact and response to a postal survey in a epidemiological study of the long-term outcome of IVF couples.MethodsThe DAIFI study is a retrospective cohort including 6,507 couples who began an IVF program in 2000-2002 in one of the eight participating French IVF centers. Medical data on all 6,507 couples were obtained from IVF center databases, and information on long-term outcome was available only for participants in the postal survey (n = 2,321). Logistic regressions were used to assess firstly factors associated with contact and secondly factors associated with response to the postal questionnaire among contacted couples.ResultsSixty-two percent of the 6,507 couples were contacted and 58% of these responded to the postal questionnaire. Contacted couples were more likely to have had a child during IVF treatment than non-contactable couples, and the same was true of respondents compared with non-respondents. Demographic and medical characteristics were both associated with probability of contact and probability of response. After adjustment, having a live birth during IVF treatment remained associated with both probabilities, and more strongly with probability of response. Having a child during IVF treatment was a major factor impacting on participation rate.ConclusionsNon-response as well as non-contact were linked to the outcome of interest, i.e. long-term parenthood success of infertile couples. Our study illustrates that an a priori hypothesis may be too simplistic and may underestimate potential bias. In the context of growing use of analytical methods that take attrition into account (such as multiple imputation), we need to better understand the mechanisms that underlie attrition in order to choose the most appropriate method.

Seven out of 10 couples treated by IVF achieve parenthood following either treatment, natural conception or adoption

“…Population and sources of data DAIFI (the French acronym for outcome after IVF) is a retrospective cohort (Troude et al, 2012). It is an exhaustive database of all 6507 couples who began IVF between 2000 and 2002 in eight French IVF centres (among the 93 IVF centres in metropolitan France).…”

“…In this paper, information from the postal questionnaire was used to explore long-term outcome among unsuccessfully treated couples. A full presentation of the postal survey is available elsewhere, including a detailed analysis of participation (Troude et al, 2012).…”

Live birth outcome, spontaneous pregnancy and adoption up to five years after undergoing assisted reproductive technology treatment

“…However, lower response rates after unsuccessful treatment have been seen in other studies . Consequently, couples responding to follow‐up questionnaires are more likely to have had successful ART treatments . Therefore, there can be a selection bias and the rate of spontaneous pregnancies can be overestimated among women with unsuccessful ART and the adoption rate underestimated in this study.…”

Men report good mental health 20 to 23 years after in vitro fertilisation treatment

“…Participation rates in long-term cohort studies are a problem, with decreasing rates during the last two decades [ 14 ]. A 2012 study of dropouts in infertility studies by Troude et al showed, not surprisingly, that having a child after treatment was the strongest reason why people dropped out of follow-up studies [ 15 ]. Therefore, there is a risk that we could have under-estimated the accurate self-perceived mental health in the men from this three-year cohort.…”