Background: Hand washing has been proven effective in reducing the spread of infectious diseases (1,2). However, evidence of the effectiveness of hand hygiene interventions in preventing infectious diseases among schoolchildren in Hong Kong is limited, especially with regard to schoolchildren with intellectual disability (ID). This is due to sensory impairment, mental retardation, social and emotional disturbance, and environmental influences (e.g. cultural differences or insufficient / inappropriate instruction) (3). Accompanying weaknesses may be identified in areas of speed of processing, working memory, phonological recoding, fine-grained auditory and/or visual processing, sequencing, organization, and motor coordination (4). All of these symptoms can make it difficult to teach simple hygiene lessons like hand washing. Schoolchildren who have developmental disabilities cannot follow complicated steps for life skills such as hand washing, but they should be given opportunities to develop skills that will prepare them to be productive community members (5). Thus, the current standardized 7-step hand washing procedure used for the general population may not be appropriate for schoolchildren with ID, as they require extra guidance and more detailed instructions for picking up basic life skills such as brushing their teeth and complicated hand washing procedure. The findings on a simplified 5-step hand hygiene program piloted in 2013 among this target group showed it to be acceptable, suitable and sustainable (6,7).
Aim: To evaluate whether the efficacy, acceptability and sustainability of a simplified hand washing program is non-inferior to the conventional 7-step hand hygiene program for students with mild intellectual disability (MID).
Design and subjects: The study will be a clustered randomized controlled non-inferior trial using repeated measures design with pre- and post-tests and follow-up measures. We will recruit 480 students aged 6-15 with MID (IQ score 50-69) from 6 MID special schools in Kowloon and the New Territories (There are only 14 MID special schools in these two areas). An equal proportion of students from each school (n=80) will be randomized to two parallel intervention arms clustered by class level. The first intervention arm will receive an 8-week simplified 5-step hand washing program, including elements of demonstration and return demonstration, a song and a video, posters, a reward system and checklists. The second intervention arm, as the active control, will receive a similar 8-week conventional 7-step hand washing program using standard education materials from the Centre for Health Protection, HKSAR. The study will be conducted in four phases: program preparation, implementation, evaluation, and long-term impact
assessment after 2 years.
Main outcome measures: Hand cleaning efficacy will be evaluated by the change in fluorescent stain rating before and after the hand washing, at pre-and post-intervention time points among the intervention and control groups. Absenteeism rates will be analyzed to evaluate the effect of hand washing programs in reducing sickness-related school absenteeism. Program sustainability will be evaluated 6 months after the intervention by the level of taught hand washing procedures recalled by the subjects, and by a fluorescent stain rating test. A focus group analysis will be conducted to compare and evaluate the acceptability and logistics involved in implementing the two different hand washing programs.
Potential implications: The results will provide evidence for formulating a standardized hand hygiene program that is suitable for schoolchildren with mild intellectual disability. It will also provide evidence to optimize the resources and procedures for implementing hand hygiene programs in special school settings. The results will encourage the development of further public health intervention programs for other vulnerable groups, especially for schoolchildren with special needs.