If consideration of study quality resolves apparent inconsistencies, then a score of 1 to 7 is assigned.
Some attempt is often made to deal with this by consideration of study quality, using published criteria such as Jadad scoring or the GRADE approach (42, 43).
Scales for quantitative assessment of study quality were very popular until empirical evidence [ 48] and theoretical considerations [ 49] indicated that scales provide invalid results.
Assessment of study quality.
Noblit and Hare's [ 15] position was that the adequacy of the study metaphors to account for the phenomena was an important quality consideration and that study quality would become apparent by how much it contributed to the synthesis.
Meta-analyses of animal data have thus included consideration of between-study heterogeneity [ 26], sensitivity analyses as appropriate [ 27] and evaluation of included study quality [ 28].
Other study quality considerations included a lack of support for alternative explanations for observed associations (e.g., bias or confounding).
This conclusion is based on Ariens et al.'s (2000) assessment of levels of evidence for systematic reviews, which includes considerations of quality and the number high-quality studies in a given area of research [ 26].
Furthermore, Chanock et al. 2007 provides a detailed list of considerations to help guide researchers when making study quality assessments [ 1].
No heterogeneity was apparent and consideration of higher quality studies did not suggest any difference in outcomes after home or outpatient physiotherapy exercise.
