Intervention (Hidden)
More specifically, we conducted our randomized controlled trial in four districts (Chandpur, Gopalgonj, Netrokona, and Sunamgonj), one district from each administration division of Bangladesh. 150 villages were randomly selected from those four districts. 30 households were randomly selected from each village based on a systematic random sampling procedure. In all 150 villages, geocoding of all selected households, household and community surveys to collect baseline information, geocoding and testing of all TWs for their level of arsenic were conducted. Villages were then randomly assigned to one of the following treatments:
Treatment 1, TW labelling: 50 were randomly assigned to this group. Here the only intervention implemented was TW labelling. In our 2014 TW census, all functioning TWs in those village were tested for arsenic. Based on that information, all TWs were labelled as safe (green) or unsafe (red) with long lasting paint similar to the Govt. of Bangladesh scheme carried out in the past . Note that TW labelling was carried out in all 150 study villages.
Treatment 2, Information campaign: A further 33 villages were randomly assigned to an information campaign/arsenic education treatment (30 households per village, 990 households in total). The information given to households focused on the negative effects of drinking arsenic contaminated water from red labelled TWs; the green labelled TWs as source of arsenic-free water, and the positive effect of drinking arsenic-free water. In half of the randomly selected households, information was given either to a male or to a female member of the household. Similar to the control villages, all TWs in these villages and the remaining villages were labelled as safe or unsafe as well.
Treatment 3, Arsenic filter in cash on delivery: In another set of randomly selected 33 villages, in addition to the information treatment described above, 990 households were offered to purchase Sono filter in cash on delivery. In addition, in half (17) of those villages selected randomly, households were offered arsenic test of the filtered water for free. Similar to the information treatment, the treated households received arsenic education/information, and all TWs in the villages were labelled as safe or unsafe.
Treatment 4, Arsenic filter on credit: In the remaining 33 villages, 990 households were offered to purchase the Sono filter under a standard microcredit contract where the loan was offered by a microfinance institution (MFI) already operating in those villages. In half (16) of the randomly selected villages, households were offered arsenic test of the filtered water for free. Similar to the cash treatment, households received arsenic education/information, and all TWs in the villages were labelled as safe or unsafe.
Note that TW labelling was carried out in all villages, and information campaign was carried out in 99 villages. In half of the households in 99 villages, information was given either to a male household member (generally the household head) or to a female household member (generally the spouse of the household head). In villages where filters were offered, in half of the villages, arsenic test of the filtered water for free was offered to households.