Study setting
The study was conducted in the Sarlahi district of Nepal, bordering the Indian state of Bihar, to the south. Residents are primarily Hindu and agrarian. In the study area, approximately half of births occur at home and half in health facilities.
Parent Trial
Data on interventions received during the peripartum period were collected through a parent trial conducted jointly by the Nepal Nutrition Intervention Project – Sarlahi (NNIPS) and our local partner organization, Nepal Netra Jyoti Sangh under the auspices of the Social Welfare Council of the Government of Nepal. Women and their newborns were enrolled in a randomized community-based trial to investigate the impact of full-body newborn massage with sunflower seed oil on newborn deaths and infections. The trial was registered at ClinicalTrials.gov (NCT01177111). The study took place in 34 Village Development Committees in the rural district of Sarlahi, Nepal, between November 2010 and January 2017.
Pregnant women were identified in the community and followed through delivery. Pregnant women participating in the trial were given clean birth kits, chlorhexidine (CHX) for application to the cut umbilical stump, deworming tablets, and counseling on early breastfeeding, thermal care, umbilical cord care, delivery care, postnatal care, and danger signs during labor and postnatal period. Mothers were visited as soon as possible following delivery, typically within 24 hours, and asked to report on the date/time of delivery, circumstances of labor and delivery, the health status of the mother and newborn, and baby’s weight. The wording of relevant delivery and immediate postpartum intervention questions administered to the mother at the first visit are listed in Supplementary File 1, Additional File 1. Additional interviews conducted throughout the first month (days 3, 7, 10, 14, 21, and 28) focused on maternal report and directly observed aspects of newborn health.
Reliability Substudy
We randomly selected a subset of mother/child pairs that participated in the parent trial and revisited these women between April and September 2016. Each selected mother was visited at home and asked to report on interventions and events in the peripartum period, including labor and delivery, immediate newborn care, postnatal care, and illness and care within the first 7 days of life using standard questions from the Demographic and Health Survey (DHS) or Multiple Indicator Cluster Survey (MICS) where applicable (see Supplementary File 2, Additional File 1). Mothers who had a singleton live birth and who were visited at home within 72 hours after delivery were eligible. We interviewed approximately equal numbers of mothers at each of seven follow-up time periods: 1, 3, 6, 9, 12, 18, or 24 months after birth (Figure 1).
Selected mothers were requested to participate in the validation substudy conducted by study staff through an oral consent process in either the Nepali or Maithili language, both of which are spoken in the area. Those who consented to participate were asked to recall care during delivery and the immediate postnatal period prior to discharge (Supplementary Table 2).
Ethical approval
The parent trial and validation substudy were approved by the Johns Hopkins Bloomberg School of Public Health Institutional Review Board in Baltimore, USA. In Nepal, approval was received from the Tribhuvan University Institute of Medicine, Kathmandu (parent trial) and the Nepal Health Research Council, Kathmandu (substudy).
Data Analysis
The reliability of each indicator was assessed by comparing what mothers reported immediately after delivery against what was reported at the follow-up survey. We assessed the reliability of fourteen indicators, including the use of items within the clean birth kit, injections given during labor / delivery, immediate newborn care, cord care, and early initiation of breastfeeding. Indicators related to immediate newborn care were defined as practices generally occurring between the delivery of the child and the delivery of the placenta. Questions about the application of CHX or other substances to the cord stump were limited to applications immediately following delivery. Early breastfeeding initiation was defined as putting the child to the breast within the first hour after delivery.
For both the initial assessment and follow-up survey, we assessed the proportion of mothers who responded “don’t know” (DK) when asked whether the intervention or practice occurred. Each mother was asked to identify each injection given during labor and delivery. If the mother reported she could not identify a specific injection and did not state oxytocin or ergometrine was given their response on “injectable Oxytocin / Ergometrine given during delivery” was classified as “DK”. The same logic was used for classifying the use of chlorohexidine. Excluding DK responses, we calculated the observed percent agreement, expected percent agreement, and kappa of maternal recall for each indicator. A sensitivity analysis maintaining DK responses as a separate response category was also conducted. The kappa statistic (κ) was used to measure the test-retest reliability of maternal report after excluding agreement due to chance. Chance expected percent agreement (pe) was defined as classification at random assuming probability equal to the overall proportion of yes and no responses at the initial (time 1) and follow-up (time 2) interview. Observed percent agreement (po) was calculated as the number of mothers reporting either receiving or not receiving a specific intervention at both the initial and follow-up survey. The kappa statistic was calculated as the difference in the expected and observed agreement over one minus the expected change agreement (Formula 1).
A κ=1 is considered perfect agreement and κ=0 is considered no agreement beyond that expected by chance alone. We interpreted κ values of greater than 0.4 as indicating moderate reliability and values greater than 0.6 as indicating strong reliability. We also calculated the proportion of women who changed their responses from 1) not receiving an intervention at the initial assessment but reported receipt during the follow-up survey (over-report), and 2) reported receiving an intervention at the initial assessment but did not report the intervention during the follow-up survey (under-report). Analyses were stratified by site of delivery, dichotomized as facility deliveries and home deliveries.
At the level of the individual respondent, we assessed potential variation in the reliability of maternal report by characteristics of the mother or birth event we hypothesized could potentially alter women’s ability to recall events around delivery. We used multivariable logistic regression to assess differences in percent agreement, over-reporting, and under-reporting of each indicator by time between birth and follow-up interview (continuous variable), child sex, maternal education (none versus any), maternal age, parity, birth location, and presence of delivery complication. Delivery complications were defined as maternal report of complications during delivery such as excessive bleeding, prolonged labor, convulsions, fever, or obstructed labor at the initial interview. We also looked for unadjusted differences in percent agreement by time since birth using binned categories for the best performing indicators.
We also assessed associations at the indicator level between the reliability of maternal recall and underlying intervention coverage or prevalence, based on initial maternal report. We calculated the unadjusted associations between intervention prevalence and indicator estimates of percent agreement, κ, the proportion of women over-reporting, and the proportion of women under-reporting each indicator. Where significant associations were identified, we calculated the proportion of variability in indicator reliability explained by differences in underlying intervention prevalence. All analyses were conducted in Stata version 14.0 (StataCorp, College Station, TX, USA).