You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Outcome", "Participant", "Intervention"].

Please return the output as a JSON object of the format: {"Participant" : ["patients with COPD", ...], "Intervention" : ["Atenolol", ...], "Outcome" : ["blood pressure", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

The effectiveness of educational interventions to enhance the adoption of fee-based arsenic testing in Bangladesh : a cluster randomized controlled trial . Arsenic ( As ) testing could help 22 million people , using drinking water sources that exceed the Bangladesh As standard , to identify safe sources . A cluster randomized controlled trial was conducted to evaluate the effectiveness of household education and local media in the increasing demand for fee-based As testing . Randomly selected households ( N = 452 ) were divided into three interventions implemented by community workers : 1 ) fee-based As testing with household education ( HE ) ; 2 ) fee-based As testing with household education and a local media campaign ( HELM ) ; and 3 ) fee-based As testing alone ( Control ) . The fee for the As test was US $ 0.28 , higher than the cost of the test ( US $ 0.16 ) . Of households with untested wells , 93 % in both intervention groups HE and HELM purchased an As test , whereas only 53 % in the control group . In conclusion , fee-based As testing with household education is effective in the increasing demand for As testing in rural Bangladesh .
{"Intervention": ["fee-based As testing with household education ( HE )", "fee-based As testing with household education and a local media campaign ( HELM )", "household education and local media", "fee-based As testing alone ( Control )", "fee-based As testing with household education", "educational interventions"], "Outcome": ["effectiveness of household education and local media", "household education is effective in the increasing demand for As testing", "HE and HELM purchased an As test", "fee-based As testing", "adoption of fee-based arsenic testing"], "Participant": ["rural Bangladesh", "Bangladesh", "452", "Randomly selected households"]}