situation between areas that were closer to the location of the large Rohingya camps and those areas farther away in the district. Accordingly, the sampling strategy for the CBPS had to meet two requirements: (i) be representative of both recently displaced Rohingya and host community households in Cox’s Bazar; (ii) stratify these population groups based on other key characteristics, such as the prevalence patterns for the camp and non-camp Rohingya displaced populations across Cox’s Bazar district.

# **3. Sampling Strategy**

# <u>Approach to define the survey strata</u>

# _Determining the prevalence of Rohingya displaced in camps and non-camp areas_

In this particular crisis, a large share of the Rohingya displaced located in camps. Key population statistics for camp-based populations were both frequently updated and made publicly available, and population quick counts in camps were implemented approximately every three months by the International Organization for Migration (IOM). These population counts were complemented by United Nations High Commissioner for Refugees (UNHCR) data on new arrivals. Together, the IOM and UNHCR data suggested that a significant share of Rohingya who had arrived during the 2017 influx continued to live in camps in the Ukhia and Teknaf sub-districts more than a year after the onset of the crisis **.** However, largely porous camp boundaries<sup>9</sup> and evidence from survey data<sup>10</sup> collected in the year after the crisis suggested that Rohingya displaced were not fully confined to camps. While some work opportunities could be generated within camps, data indicated that many Rohingya were either leaving and returning to camps daily for work purposes or else relocating entirely outside camps to pursue work.<sup>11</sup> For the purposes of obtaining a representative survey of Rohingya displaced it was important to determine the true prevalence of displaced Rohingya outside camps.

Due to the absence of a comprehensive sampling frame for Rohingya outside camps, IPA Bangladesh had conducted a quick population count exercise which provided an opportunity to assess the likely prevalence

> 9 Based on satellite imagery, anecdotal evidence from multiple local actors, and field observations.

> 10 The December 2017 Rohingya Emergency Vulnerability Assessment (REVA) and June 2018 Community-Based Monitoring System (CBMS) surveys, administered by the World Food Programme (WFP), found that over half of Rohingya displaced reached by telephone surveys reported working, despite a formal ban on work for Rohingya displaced (World Bank 2019).

> 11 It was evident from field observations and reports that camp boundaries were largely porous. In addition, other survey data collected in the year after the crisis suggested that Rohingya displaced were not fully confined to camps. This was further corroborated by data collected by the World Food Programme as part of the Rohingya Emergency Vulnerability Assessment (REVA) in December 2017 and the <mark>Community-Based Monitoring System (C</mark> BMS) surveys in June 2018. Over half of Rohingya displaced reached by phone surveys for these assessments reported working, despite a formal ban on work for Rohingya displaced (World Bank 2019). These data suggested that some Rohingya displaced were either leaving and returning to camps every day for work, or else relocating entirely outside camps to pursue work opportunities.

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