2.4. Quality Assessment
The quality of included studies was assessed using“ Quality Assessment of
Controlled Intervention Studies” 19 developed by The National Heart, Lung, and Blood Institute( NHLBI) and Research Triangle Institute International Jointly. It includes 14 criteria that need to be assessed, which refer to the internal validity of each of the included studies based on their methodology. All of the criteria were scored with either yes, no, Cannot Determine( CD), or Not Applicable( NA). A“ yes” was given one point, whereas a“ no” was given a score of 0.
No standard for a good, moderate, or poor study was given. Hence, a study obtaining a score of 11 / 14 or higher was defined as a good quality study, meanwhile studies receiving a score of 7 / 14 or less were defined as poor studies. A score between 7 and 11 out of 14 was defined as moderate.
Two reviewers( RA, OEY) independently analyzed the included studies based on the quality assessment criteria. If the ratings differed, the articles were discussed until a common consensus was reached.
3. Results 3.1. Research Findings and Study Selection
The search terms were applied to all of the 6 search engines and databases mentioned earlier. Titles and abstracts were screened and relevant titles were selected. After removal of duplicates, a total of 61 studies were obtained from the database search. Initial screening of abstracts against eligibility criteria excluded 41 studies. A further 14 trials were excluded after reading full text articles as they did not have a viable study design based on preset inclusion and exclusion criteria. The comprehensive data on the study selection process can be seen in Figure 1.
The six clinical trials selected in this systematic review were conducted by Dayan, et al.( 2013), 20 HSS, et al.( 2013), 21 Lanata, et al( 2012), 22 Sabchareon, et al( 2012), 23 Villar, et al( 2013), 24 and Leo, et al( 2012). 25