<prompt> Most important epidemiological tool used for assessing disability in children isActivities of Daily Living ADL scale.Wings Handicaps, Behaviour and Skills HBS ScheduleBinet and Simon IQ testsPhysical Quality of Life Index PQL 1  <response>: There have been many attempts to measure or record in standardized form the aspects of behaviors, psychological function and social performanceOne of the most important is Wings Comprehensive Handicaps, II Behavior and Skills HBS scheduleIt has been used in epidemiological studies to assess the total child population in terms of detailed scales of specific abilities and disabilities.It is essentially a research tool, but Wing has developed from it a small practical schedules for use in service contexts using what has emerged as the most important aspect of mobility, communication and social interaction.The resulting short disability assessment schedule is being used in several communities as a source of high quality routine data for total population. 