Provider-mother interactions are associated with birth outcome misclassifications in household surveys: A case-control study in Guinea-Bissau

Background: Approximately 4.4 million children die peripartum annually, primarily in low- and middle-income countries. Accurate mortality tracking is essential to prioritising prevention efforts but is undermined by misclassification between stillbirths (SBs) and early neonatal deaths (ENNDs) in household surveys, which serve as key data sources. We explored and quantified associations between peripartum provider-mother interactions and misclassification of SBs and ENNDs in Guinea-Bissau. Methods: Using a case-control design, we followed up on women who had reported a SB or ENND in a retrospective household survey nested in the Bandim Health Project's Health and Demographic Surveillance Systems (HDSS). Using prospective HDSS registration as the reference standard, we linked the survey-reported deaths to the corresponding HDSS records and cross-tabulated SB/ENND classification to identify cases (discordant classification between survey and HDSS) and controls (concordant classification). We further interviewed cases and controls on peripartum provider-mother interactions and analysed data using descriptive statistics and logistic regressions. Results: We interviewed 278 women (cases: 63 (23%); controls: 215 (77%)). Most cases were SBs misclassified as ENNDs (n/N = 49/63 (78%)). Three-fourths of the interviewed women reported having received no updates on the progress of labour and baby's health intrapartum, and less than one-fourth inquired about this information. In comparison with births where women did inquire for information, misclassification was less likely when women did not inquire and recalled no doubts about progress of labour (odds ratio (OR) = 0.51; 95% confidence interval (CI) = 0.28-0.91), or baby's health (OR = 0.54; 95% CI = 0.30-0.97). Most women reported that service providers' death notifications lasted <5 minutes (cases: 23/27 (85%); controls: 61/71 (86%)), and most often encompassed neither events leading to the death (cases: 19/27 (70%); controls: 55/71 (77%)) nor causes of death (cases: 20/27 (74%); controls: 54/71 (76%)). Misclassification was more likely if communication lasted <1 compared to 1-4 minutes (OR = 1.83; 95% CI = 1.10-3.06) and if a formal service provider had informed the mother of the death compared to a family member (OR = 1.57; 95% CI = 1.04-2.36). Conclusions: Peripartum provider-mother interactions are limited in Guinea-Bissau and associated with birth outcome misclassifications in retrospective household surveys. In our study population, misclassification led to overestimated neonatal mortality.