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Designing and testing nudges to improve school handwashing in the Philippines

The long walk from the toilet stall to the handwashing station in a classroom in Zamboanga del Norte ©IDinsight/Nhu Le

Handwashing Policy Brief - 610 KB

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Handwashing one-pager - 990 KB

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Decision-maker’s challenge

UNICEF first began working with IDinsight to identify why their WASH program wasn’t working effectively. In addition, UNICEF had an opportunity to work with the Department of Education to improve children’s handwashing at scale across the Philippines — thereby significantly reducing the likelihood of children dying or getting sick from preventable diseases.

In the first two phases of the engagement, IDinsight evaluated a different intervention aimed at increasing handwashing through a teacher-led behavior change program, but found that it didn’t increase handwashing rates enough to justify scale up. 

Given the exciting results seen from behavioral “nudges” built into the handwashing environment in other contexts, we suggested that UNICEF and DepEd adapt and test this intervention in the Philippines. Working together, we adapted the nudges to address the primary barriers to handwashing among children in the Philippines, which our previous studies had found to be forgetfulness and more broadly, a lack of habit formation.

Impact opportunity

School children in the Philippines suffer from a high burden of preventable diseases, with hygiene deficiencies identified as a common cause. Handwashing with soap is considered to be one of the most effective measures to reduce respiratory tract infections and diarrhea and prevent the transmission of infectious diseases. IDinsight’s previous research in Philippine public schools found that independent handwashing with soap (iHWWS) rates are below 10%, even when adequate facilities are available. But targeted behavior change campaigns conducted by teachers did not lead to meaningful changes in handwashing behavior, despite strong implementation. 

Therefore, IDinsight designed and evaluated an intervention to instill the habit of regular handwashing by pupils in Philippineschools. Our goal was to identify a successful intervention that could be incorporated into the national WASH in Schools policy that directly impacts over-40-million children in the Philippines who attend public schools.1

Pilot installation to compare painted footpath with spray-painted footprints and spray-painted footprints only ©IDinsight/Nhu Le

Our approach

IDinsight work included: 

  1. Intervention design: We created nudges suitable to the Philippine context by drawing on previous studies on handwashing nudges, conducting scoping visits, and piloting nudge designs in Philippine schools.
  2. Intervention implementation: To ensure that the nudges were installed in schools according to our design specifications, we managed a local team.
  3. Decision-focused evaluation: To assess whether these nudges improve handwashing rates, we conducted an impact evaluation using a clustered randomized controlled trial. Half of the 132 schools were randomly selected to receive the nudges intervention; the remaining half served as control. We conducted handwashing observations among pupils in grades 1-3 and 4-6 of both genders, in order to evaluate the potential differential effects based on age or gender. The primary objective of the evaluation was to estimate the effect of the intervention on independent handwashing with soap after toilet use by pupils. 
  4. Policy-shaping advisory support: We hosted several presentations, workshops, and working sessions with policy makers from DepEd, UNICEF, and other relevant stakeholders (like the Department of Health) to explain our findings’ implications for policy makers.

Specifically, we evaluated the effectiveness of four nudges:

  1. Rotating posters in the bathroom that motivate and remind students to wash their hands.
  2. Footpath with footprints painted on the floor, designed to lead students from the toilet to the handwashing station
  3. Arrow pointing to soap dish, to carve out physical space for soap by handwashing station and to remind students to use soap to wash their hands
  4. “Watching” eye sticker, to subconsciously motivate students to wash hands through peer pressure
Installed nudges in treatment classrooms across Zamboanga del Norte ©IDinsight/Project surveyors

The results

We found that the low-cost handwashing nudges drove longer-lasting, “sticky” behavior change in independent handwashing with soap after toilet use by pupils. Four months after nudges were installed, we found that students’ handwashing rates increased by 17 percentage points compared to students in schools without the nudges. This is equivalent to an increase of 148 percent. The nudges also led to improved access to functional handwashing facilities. Compared to students who didn’t receive nudges, students in schools with nudges were slightly more likely to have access to a functional handwashing facility near toilets, and 38 percent more likely to have access to a facility with soap. This suggested that the contextual and visual cues we installed helped trigger habit formation.

Given nudge installations cost relatively little ($60 USD per school), we recommended that the Department of Education scale up school-based nudges in elementary schools that have minimum WASH infrastructure in the Philippines as a part of its WinS policy. The recommended infrastructure requirements are: functional toilets, functional handwashing stations, water availability at least some hours of the day (running or stored), and dedicated school funds for soap. We also recommended that the nudges, which can improve handwashing rates after toilet use, be utilized in conjunction with other infection prevention and mitigation measures to ensure a safer environment in schools for students during the COVID-19 pandemic. 

Based on our findings, DepEd is including the nudges as part of a recommended package of infrastructure improvements for eligible schools when they reopen after COVID closures.


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