Aims: While methadone maintenance treatment (MMT) has been shown to be effective in reducing opioid drug harm less is known about what encourages people to enter and remain in this treatment. A literature review indicated that multidimensional pressures to enter treatment, e.g. deteriorating physical health or family conflict, might be important. While efforts have been made to measure these pressures, further work was required to enhance the reliability and validity of an instrument which had been developed, i.e. the STEP-UP. The aim of the study was therefore to undertake an examination of psychometric properties of the STEP-UP.
Design: The study used a test re-test design to analyse test re-test reliability and internal consistency. Content validity was determined from the examination of the STEP-UP by members of an expert panel.
Setting: The setting comprised three NHS drug treatment services in the West of Scotland
Participants: Twenty six participants were recruited all of whom all had been undertaking MMT for at least six weeks.
Measurement: The original version of the STEP-UP comprised 121 items in 20 subscales. Each item invited one of four responses yielding a score of 0, 1, 2 or 3. The STEP-UP was administered to the study participants on two occasions two weeks apart
Findings: The analyses of the reliability and internal consistency of the STEP UP resulted in the deletion of 51 items. The content validity analysis resulted in the deletion of some items and the rewording of others. This resulted in a substantially modified questionnaire comprising 46 items with demonstrable reliability and validity. This shorter questionnaire should be easier to administer and should reduce the risk of bias due to participant fatigue.
Professor Hazel Watson, Glasgow Caledonina University Dr Angus McFadyen, AKM-Stats Dr Dave Johnson, Consultant Psychiatrist, NHS Highland Dr Susan Kerr, Glasgow, Caledonian University
Conflicts of interest:
Part funded by Argyll and Clyde Health Board and part self funded, no declaration of interest.