A modified Timeline Followback assessment to capture alcohol exposure in pregnant women: Application in the Safe Passage Study

Abstract

Prenatal alcohol exposure (PAE) has been linked to poor pregnancy outcomes, yet there is no recognized standard for PAE assessment, and the specific effects of quantity, frequency, and timing remain largely unknown. The Safe Passage Study was designed to investigate the role of PAE in a continuum of poor peri- and postnatal outcomes. The objective of this manuscript is to describe the rationale for, and feasibility of, modifications to the traditional Timeline Followback (TLFB) for collecting PAE information in a large cohort of pregnant women. Participants from the Northern Plains region (in the United States) and Cape Town, South Africa, were followed prospectively using a modified 30-day TLFB interview, administered up to five times, to obtain detailed PAE information. Required modifications for our population included capturing information regarding sharing, type/brand, container size, and duration, in order to accurately record the amount of alcohol consumed. PAE status was defined for 99.9% of the 11,892 enrolled pregnancies at least once during pregnancy and for 92% across all trimesters. Of 53,823 drinks reported, 98% had all items necessary for standard drink computation. Sharing was reported for 74% of drinks in Cape Town, South Africa and for 10% in the Northern Plains. Compared to referent values from the traditional TLFB, 74% and 67% of drinks had different alcohol-by-volume and container size, respectively. Furthermore, a statistically significant difference was found between the number of containers reported and the number of standard drinks computed, using information from the modified TLFB. This is the first study of this size to wholly encompass all of these changes into a single measure in order to more accurately calculate daily consumption and assess patterns over time. The methods used to collect PAE information and create alcohol exposure measures likely increased the accuracy of standard drinks reported and could be generalized to other populations.

Drinking and smoking patterns during pregnancy: Development of group-based trajectories in the Safe Passage Study

“…The prospective design of the Safe Passage study reduced recall error, and a significant effort was made to reduce social stigma by building rapport and a sense of trust between the participants, community, and study staff and utilizing a certificate of confidentiality (Dukes et al, this issue). We found that 61% of women reported a positive history of drinking, 56% reported a positive history of smoking, and 38% reported a positive history of dual exposure during pregnancy, compared to lower prevalences of 9.4% and 15.4% drinking and smoking during pregnancy, respectively, reported in the literature (Slater et al, 2015).…”

“…Our study population required modification to the TLFB to include collection of additional details on sharing, type/brand of beverages consumed (to assign specific alcohol by volume), and container sizes (Dukes et al, this issue). Prenatal smoking exposure information was obtained by querying how often the participant smoked a tobacco cigarette using graduated frequency response options (i.e., none, monthly or less, 2–4 days per month, 2–3 days per week, 4–6 days per week, and 7 days per week) and the number of cigarettes smoked on a typical day.…”

“…Prenatal smoking exposure information was obtained by querying how often the participant smoked a tobacco cigarette using graduated frequency response options (i.e., none, monthly or less, 2–4 days per month, 2–3 days per week, 4–6 days per week, and 7 days per week) and the number of cigarettes smoked on a typical day. Collection of drinking and smoking exposure was through interviews administered by trained research staff (Dukes et al, this issue). Depending on the timing of participant enrollment, exposure information was collected up to four times during pregnancy: at recruitment (6+ gestational weeks), 20–24 weeks, 28–32 weeks (random subset only), and 34+ weeks, and also at 1 month post-delivery, each covering the 30-day reference period prior to the last reported drinking or smoking day.…”

The association of prenatal alcohol exposure on the cognitive abilities and behaviour profiles of 4‐year‐old children: a prospective cohort study

“…The study investigators modified the standard TLFB to capture further information regarding sharing, type/brand of beverage, and container size for use in the calculation of standard drinks. Detailed description of the alcohol exposure assessments has been published elsewhere …”

The K nearest neighbor algorithm for imputation of missing longitudinal prenatal alcohol data

“…The Safe Passage Study conducted by the Prenatal Alcohol and SIDS and Stillbirth Network (PASS) was a prospective investigation of effects of alcohol exposure on multiple fetal and infant outcomes in Cape Town, South Africa and the Northern Plains, USA [9]. In this study, alcohol data were collected using a modi cation of the Timeline Followback Method (TLFB) [10], in which mothers recorded drinking data on their last known drinking day and then, for the 30 days prior. While this method was deemed the best selfreport system available, the approach necessarily generated a variable amount of missing data.…”