Items | Description | Score | ||||
---|---|---|---|---|---|---|
Reporting | Kwak et al. [26] | Steinberg et al. [23] | Rolland et al. [25] | Stevens and Killeen [24] | Francese et al. [27] | |
Hypothesis | Is the hypothesis/aim/objective of the study clearly described? | 1 | 1 | 1 | 1 | 1 |
Main outcomes | Are the main outcomes to be measured clearly described in the “Introduction” or “Methods” section? | 0 | 1 | 1 | 1 | 1 |
Included patients characteristics | Are the characteristics of the patients included in the study clearly described? | 0 | 1 | 1 | 0 | 0 |
Interventions of interest | Are the interventions of interest clearly described? | 1 | 1 | 1 | 0 | 0 |
Distribution | Are the distributions of principal confounders in each group of subjects to be compared clearly described? | 1 | 2 | 2 | 1 | 1 |
Main findings | Are the main findings of the study clearly described? | 1 | 1 | 1 | 1 | 1 |
Random variability | Does the study provide estimates of the random variability in the data for the main outcomes? | 1 | 1 | 1 | 0 | 1 |
Adverse events | Have all important adverse events that may be a consequence of the intervention been reported? | 0 | 1 | 1 | 0 | 0 |
Characteristics of patients lost to follow-up | Have the characteristics of patients lost to follow-up been described? | 0 | 0 | 1 | 0 | 1 |
Probability values | Have actual probability values been reported (e.g. 0.035 rather than <0.05) for the main outcomes except where the probability value is less than 0.001? | 0 | 1 | 1 | 1 | 1 |
External validity | ||||||
Representativity of the participants | Were the subjects asked to participate in the study representative of the entire population from which they were recruited? | 0 | 0 | 1 | 1 | 1 |
Representativity of the prepared subjects | Were those subjects who were prepared to participate representative of the entire population from which they were recruited? | 0 | 0 | 0 | 0 | 0 |
Representativity of the staff, places and facilities | Were the staff, places, and facilities where the patients were treated, representative of the treatment the majority of patients receive? | 0 | 0 | 1 | 0 | 0 |
Internal validity bias | ||||||
Blind study subjects | Was an attempt made to blind study subjects to the intervention they have received? | 0 | 0 | 0 | 0 | 0 |
Blind staff | Was an attempt made to blind those measuring the main outcomes of the intervention? | 0 | 1 | 1 | 0 | 0 |
“Data dredging” | If any of the results of the study were based on “data dredging,” was this made clear? | 1 | 1 | 1 | 0 | 1 |
Adjustment of the analyses | In trials and cohort studies, do the analyses adjust for different lengths of follow-up of patients, or in case–control studies, is the time period between the intervention and outcome the same for cases and controls? | 1 | 1 | 1 | 1 | 1 |
Statistical tests | Were the statistical tests used to assess the main outcomes appropriate? | 1 | 1 | 1 | 1 | 0 |
Compliance | Was compliance which the intervention/s reliable? | 0 | 1 | 1 | 0 | 0 |
Validity and reliability of the main outcomes | Were the main outcome measures used accurate (valid and reliable)? | 0 | 1 | 0 | 0 | 1 |
Internal validity confounding | ||||||
Subjects recruited from the same population | Were the patients in different intervention groups (trials and cohort studies) or were the cases and controls (case–control studies) recruited from the same population? | 0 | 1 | 1 | 1 | 1 |
Subjects recruited over the same period of time | Were the patients in different intervention groups (trials and cohort studies) or were the cases and controls (case–control studies) recruited over the same period of time? | 0 | 0 | 1 | 1 | 1 |
Randomization | Were study subjects randomized to intervention groups? | 1 | 1 | 1 | 1 | 1 |
Randomized intervention assignment | Was the randomized intervention assignment concealed from both patients and health care staff until was complete and irrevocable? | 0 | 0 | 1 | 0 | 0 |
Adequate adjustment for confounding | Was there adequate adjustment for confounding in the analyses from which the main findings were drawn? | 1 | 1 | 1 | 0 | 0 |
Losses of patients to follow-up | Were losses of patients to follow-up taken into account? | 0 | 0 | 1 | 0 | 0 |
Power | ||||||
Clinically important effect | Did the study have sufficient power to detect a clinically important effect where the probability value for a difference being due to chance is less than 5%? | 0 | 0 | 1 | 1 | 0 |
Total score | 10 | 19 | 25 | 12 | 14 |