Estimating Displacement Status, Socio-Demographic Profiles, and Food Insecurity among Internally Displaced Persons in Biu Local Government Area, Borno State, Nigeria Using Respondent-Driven Sampling

Abstract

The escalating crisis of internal displacement in north-eastern Nigeria, driven primarily by Boko Haram insurgency, has generated a large and largely hidden populations of Internally Displaced Persons (IDPs) residing in host communities. Estimating the size and characteristics of this population is methodologically challenging due to the absence of a formal sampling frame and the concealed nature of IDPs in host settings. This study applied Respondent-Driven Sampling (RDS) to recruit 650 IDPs across three communities; Mirringa, Biu, and Buratai in Biu Local Government Area, Borno State, Nigeria. Two estimators were employed: the Naive estimator (Heckathorn, 1997), grounded in with-replacement sampling assumptions, and a Weighted RDS estimator developed under without-replacement sampling assumptions. The study estimated displacement status, socio-demographic profiles, types of support received, and food insecurity experiences. Results revealed that 97.6% of respondents were confirmed IDPs, with conflict and violence as the primary driver of displacement (94.5%). The majority had been forcibly displaced more than five times (63.2%) and were living in severely inadequate shelter conditions. Food insecurity was pervasive, with 97.6% worried about food sufficiency and 94.3% having skipped meals in the past 30 days. Only 60.6% had received any form of post-displacement support, predominantly food assistance. Weighted estimates consistently differed from unweighted figures, confirming the importance of accounting for differential sampling probabilities in RDS-based studies of hidden populations.