Involvement of trial competencies

This section contains the following:

Introduction
Trial competencies to consider

Introduction

The MRC Framework for Developing and Evaluating Complex Intervention to Improve Health (MRC, 2000) has influenced the way researchers think about complex interventions. Before trial development the MRC advises that several phases occur; 1.theoretical, 2. modelling, 3. exploratory trials. In order to explore these it is useful to involve other trial competencies from the social, behavioural and health sciences.

Trial competencies to consider

Health Economics

A health economist should be involved if and economic evaluation is necessary. The aim of an economic evaluation is to determine the value of the goods or service in order to aid the decision making process in a trial. The economic evaluation should identify, measure, and value the relevant costs and consequences of the programme or intervention being analysed. (see Health Economics)

Health Psychology

The study of psychological and behavioural processes in health, illness and health care (Johnston 1994), where psychological processes' including perceptions, thoughts and memories ('cognitions') and feelings ('emotions'). Health psychology thus relates to trials that aim to build evidence concerning (1) primary prevention interventions (e.g. screening); (2) drug and non-drug interventions to treat illness (e.g. surgical procedures); and (3) implementation interventions (e.g. to increase uptake by health professionals of evidence-based practice).

Qualitative Research

Qualitative research methods can be used to improve the explanatory power of RCTs and illuminate and aid our understanding of a trial as a social construction. A pragmatic RCT is only designed to answer whether or not an intervention is effective. Sub group analyses may help to answer questions such as 'Why does this intervention work or not work?' and 'For whom does it work best?' but the large numbers of subjects required to have sufficient statistical power to undertake such analyses often make them prohibitive. Qualitative research methods, on the other hand, do not suffer from such constraints. They are particularly good at answering what and why type questions and can also be used to answer other supplementary questions such as 'Will this intervention work in a variety of health care settings?' and 'What might be the problems in trying to introduce this intervention throughout a health service?' (Campbell R and Pope C, 2000).

Statistics

The success of any trial depends on the quality of the data collected. Statistical input is required for the designing of the data collection strategy so that the correct data is collected at the right time points. A trial rarely needs full -time statistical support but input will be required particularly in the planning phase, monitoring the quality of the data, interim and final analysis. (see Statistics).