Total mean scores on AMSTAR ranged from 2 to 10 (out of a maximum score of 11) with a mean percentage score of 55.1%. The total mean quality scores on OQAQ ranged from 3 to 8 (out of a maximum score of 9) with a mean percentage score of 63.6%. The overall scores for the global assessment instrument (item 10 in OQAQ) ranged from 1 to 6 (out of a maximum score of seven) with a mean of 3.3 (95% CI: 2.9, 3.6), and overall scores using the self-developed 100-point rating scale ranged from 15 to 73 with a mean of 47.6 (95% CI: 43.4, 51.7).