Abstract:
The current knowledge about how children with disabilities (including those who use AAC) participate over time within home and community settings such as recreation, leisure and sporting activities is based predominantly on cross-sectional data or on studies that are limited to two measuring points and not longitudinal research that follows children over time. It is rather complex to determine causal relationships from cross-sectional studies. Furthermore, the limitations of narrow measures of participation are that they do not tell us how participation can change across important points in the lifespan of these populations. More longitudinal studies are therefore needed to examine the participation trajectories over time, although it is not yet clear to what extent longitudinal research on participation has been conducted with children with disabilities. It is also not known how well those that do undertake longitudinal research are based on the latest quality guidelines of what this type of research should consider in terms of the theory, design and analysis of longitudinal participation research. The aim of this systematic review was therefore to explore the state of the art of longitudinal research on activity performance or participation in home and community environments for children and youth with disabilities in terms of the best known theoretical, methodological and analytical guidelines available for this type of design. Twenty-two studies were identified that fulfilled the inclusion criteria. The studies were described with regard to the participants, type of design, duration of the study, country in which the study took place, the change outcome of interest, the measurement instruments used, and the child role in data collection. Furthermore, the studies were described in relation to (i) how well these longitudinal studies hypothesise a theory of change in terms of form, level, duration or predictors to guide their research (ii) how well these longitudinal studies take into account methodological and design considerations (measurement waves, timing and observations, sampling, attrition and measurement validity) when examining change in participation in home and community activities, and (iii) what analytic methods these studies use to document change. Attention is drawn to the gaps in the literature in terms of how studies are conducting longitudinal research. The importance of precision and insight to theories is discussed, as is the need for longitudinal research in LAMI countries and in the field of AAC.