Table 2.

AXIS Appraisal of Studies.

Author/Year	Anderson 2009	Anderson 2011	Manuel 2002	Lee 2017	Mitchell 2012	McKay 2013	Houle 2010	Padaki 2018	Piatt 2016	Pot 2014
Question
Were the aims/objectives of the study clear?	●	●	●	●	●	●	●	●	●	●
Was the study design appropriate for the stated aim(s)?	●	●	●	●	●	●	●	●	●	●
Was the sample size justified?	●	●	●	●	●	●	●	●	●	●
Was the target/reference population clearly defined? (Is it clear who the research was about?)	●	●	●	●	●	●	●	●	●	●
Was the sample frame taken from an appropriate population base so that it closely represented the target/reference population under investigation?	●	●	●	●	●	●	●	●	●	●
Was the selection process likely to select subjects/participants that were representative of the target/reference population under investigation?	●	●	●	●	●	●	●	●	●	●
Were measures undertaken to address and categorize non-responders?	●	●	●	●	●	●	●	●	●	●
Were the risk factor and outcome variables measured appropriately to the aims of the study?	●	●	●	●	●	●	●	●	●	●
Were the risk factor and outcome variables measured correctly using instruments/measurements that had been trailed, piloted or published previously?	●	●	●	●	●	●	●	●	●	●
Is it clear what was used to determined statistical significance and/or precision estimates? (e.g., p-values, confidence intervals)	●	●	●	●	●	●	●	●	●	●
Were the methods (including statistical methods) sufficiently described to enable them to be repeated?	●	●	●	●	●	●	●	●	●	●
Were the basic data adequately described?	●	●	●	●	●	●	●	●	●	●
Does the response rate raise concerns about non-bias?	●	●	●	●	●	●	●	●	●	●
If appropriate, was information about non-responders described?	●	●	●	●	●	●	●	●	●	●
Were the results internally consistent?	●	●	●	●	●	●	●	●	●	●
Were the results presented for all the analyses described in the methods?	●	●	●	●	●	●	●	●	●	●
Were the authors’ discussions and conclusions justified by the results?	●	●	●	●	●	●	●	●	●	●
Were the limitations of the study discussed?	●	●	●	●	●	●	●	●	●	●
Were there any funding sources or conflicts of interest that may affect the authors’ interpretation of the results?	●	●	●	●	●	●	●	●	●	●
Was ethical approval or consent of participants attained?	●	●	●	●	●	●	●	●	●	●

Green: strong/yes; Yellow: moderate/not specifically reported; Red: weak/no.