Barriers and Drivers to Adoption and Use of a Household Ultraviolet Water Disinfection System: A Randomized Stepped Wedge Trial in Rural Mexico

Fermin ReygadasEnergy and Resources Group, UC Berkeley

reygadas@berkeley.edu

UC Berkeley Collaborators:Joshua Gruber, Division of EpidemiologyJack Colford, Division of Epidemiology

Kara Nelson, Civil and Environmental EngineeringIsha Ray, Energy and Resources Group

(Tovar, R. et al. 2005;    Reygadas, F. et al. 2007;    Photo Credit: Moreno, E. & Fundacion Cantaro Azul)

‐ Operates at fast flow rate of 5 liters / minute‐ Easy to use and does not change taste of water‐ Requires electricity, clear water, and safe storage

Mesita Azul: Water Disinfection at the Household Level

Baffle homogenizes flow

15W UV lamp

NeedsAssessment

Community Presentation

Installation

Follow Up Visits

Mesita Azul Program

Research Questions:

• What levels of adoption and use can be achieved with ultraviolet disinfection at the household level?

• Can small changes in the levels of convenience of household water treatment programs lead to significant increases in adoption and use outcomes?

Great Barriers    Small  Hassles

(Impact Eval of MA: Gruber, J. et al. 2013;     Behavioral Econ: Bertrand, M. et al. 2006;     Images: CAWST)

Research Location:Baja California Sur, Mexico

Research Design:Stepped‐Wedge Cluster Randomized Trial

Clusters    Baseline        Step 1         Step 2        Step 3       Step 4         Step 5        Step 6

1‐4                 0                 0                    0 0 0                  0                 0

5‐8 0                 0              0 0 0                  0                 0

9‐12               0                 0              0 0                0                  0                 0

13‐16 0                 0                    0 0           0                  0                 0

17‐20 0                 0                    0 0           0                 0                 0

21‐24 0                 0                    0 0             0            0           0

Before Intervention

After Intervention

0  = Observation

X   = Intervention

X

X

X

X

X

X

Developed Compliance Framework that Maps Key HWT Outcomes:

Adoption of Safe Water Practice

Knowledge of Safe Water Practice

Access to Safe Water

Habit of Safe Water Practice

Exclusive Use of Safe Water

Disaggregated Key Outcomes:

Adoption of Safe Water PracticeAcquisition

Acq. Agreement

Knowledge of Safe Water PracticeProcurement

Consumption

Access to Safe WaterProcurement

Consumption

Habit of Safe Water PracticeProcurement

Consumption

Exclusive Use of Safe WaterProcurement

Consumption

HH vs. Community

Adapted Compliance Framework to the Mesita Azul Program:

Adoption of Safe Water PracticeAcquisition Mesita Azul (MA) was installed in household

Acq. Agreement Paid contribution in full

Knowledge of Safe Water PracticeProcurement Operator has minimum basic knowledge and skills in using MA

Consumption Interviewee differentiates treated and safely stored sources from others

Access to Safe WaterProcurement MA is present at accessible location and in working condition

Consumption Water treated with MA and safely stored (SS) is present at time of visit

Habit of Safe Water PracticeProcurement Uses MA to treat water at least once every five days

Consumption MA‐SS is most common source & Last glass served from MA+SS

Exclusive Use of Safe WaterProcurement Not documented

Consumption Has only consumed water from MA‐SS in past 7 days

HH vs. Community Not documented

Acquired Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Can small changes lead to significant increases in compliance?

Tested Basic vs. Enhanced Programs

Clusters    Baseline        Step 1         Step 2        Step 3       Step 4         Step 5        Step 6

1‐4                 0                 0                    0 0 0                  0                 0

5‐8 0                 0              0 0 0                  0                 0

9‐12               0                 0              0 0                0                  0                 0

13‐16 0                 0                    0 0           0                  0                 0

17‐20 0                 0                    0 0           0                 0                 0

21‐24 0                 0                    0 0             0            0           0

Before Intervention

After Intervention

0  = Observation

XB = Basic ProgramXE = Enhanced Program

XBXE

XBXE

XBXE

XBXE

XBXE

XBXE

Barriers Basic  Program Enhanced  Program

Information Regional water quality results Individual water quality results

Economic Six month system guarantee Satisfaction guarantee (money back)

OperatorBehavior

Train 1 person per household Train 2 people per household

ConsumerBehavior

1 safe storage container 2 safe storage containers

HabitFormation

Follow up every 6 months Follow up within 1 month

Adoption and Use Barriers

Compliance and Cost‐Effectiveness Results

** => p<0.05*   => p<0.1

Results indicate that investing in minor program components that reduce behavior barriers can improve adoption, use, and cost‐effectiveness outcomes.

Outcome Metric Basic Enhanced Adj. RiskDifference

Adoption 70% 81% 7% *

Habit of Consumption 34% 47% 8% **

Adoption ($/hh) $112 $127 +$15

Habit of Consumption ($/hh) $226 $219 ‐ $ 7

Acquired Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Acquired Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Acquired Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Conclusions:

• The Mesita Azul program significantly increased the habit of consuming treated and safely‐stored water

• Small improvements in convenience can lead to statistically significant increases in compliance (while improvements last)

• Using a comprehensive compliance framework that combines impact evaluation with formative research can help us better understand barriers and drivers to safe water practices

Barriers and Drivers to Adoption and Use of a Household Ultraviolet Water Disinfection System: A Randomized Control Stepped Wedge Trial in 

Baja California Sur, Mexico

Fermin ReygadasEnergy and Resources Group, UC Berkeley

reygadas@berkeley.edu

Water and Health Conference, UNCOctober 15th, 2013

Acknowledgments: Ian B, Cintia L, Hector C, and Saul H, at Fundacion Cantaro Azul, MexicoSustainable Products and Solutions Program, UC Berkeley Consejo Nacional de Ciencia y Tecnología, MexicoBlum Center for Developing Economies, UC Berkeley

Acquired Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

UV Disinfection

• Effective in inactivating pathogens• Efficient• High flow rates• Does not impact taste• No disinfection byproducts

• No residual disinfection• Requires electricity• Does not remove physical or 

chemical contaminants• Water absorbance lowers dose

Advantages Drawbacks

Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Procuring Consuming Procuring Consuming Procuring Consuming Consuming

Adoption Knowledge Access Habit Exclusive

Developed Compliance Framework with Summative & Formative Goals:

Adoption of Safe Water Practiceo Acquisitiono Compliance

Knowledge of Safe Water Practiceo Procuremento Consumption

Access to Safe Watero Procuremento Consumption

Habit of Safe Water Practiceo Procuremento Consumption

Exclusive Use of Safe Watero Procuremento Consumptiono HH vs. Community

Compliance Framework to Assess Summative & Formative Goals:

Adoption of Safe Water PracticeAcquisition

Compliance

Knowledge of Safe Water PracticeProcurement

Consumption

Access to Safe WaterProcurement

Consumption

Habit of Safe Water PracticeProcurement

Consumption

Exclusive Use of Safe Water

Procurement

Consumption

HH vs. Community

Compliance Framework to Assess Summative & Formative Goals:

Adoption of Safe Water PracticeAcquisition

Compliance

Knowledge of Safe Water PracticeProcurement

Consumption

Access to Safe WaterProcurement

Consumption

Habit of Safe Water PracticeProcurement

Consumption

Exclusive Use of Safe Water

Procurement

Consumption

HH vs. Community