Table 1: Checklist for quality of studies included in review.

Study Explicit aims Adequate and justified sample size Justification of sample size representation Clear inclusion and exclusion criteria Valid measurement of PND Adherence and drop our rate specified Adequate description of data Appropriate statistical analysis Delivery of method specified
Milgrom, et al. [37] Yes Yes Yes Yes Yes Yes Yes Yes Yes
O'Mahen, et al. [23] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Armstrong & Edwards [70] Yes Yes Yes Yes Yes No Yes Yes Yes
Caramlau, et al. [71] Yes Yes Yes Yes Yes No No No Yes
O'Mahen, et al. [19] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Chabrol, et al. [48] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Milgrom, et al. [16] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Copper, et al. [42] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Boath, et al. [18] Yes Yes Yes No Yes No Yes Yes Yes
Prendergast, et al. [53] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Ho, et al. [55] Yes Yes No Yes Yes Yes No Yes Yes
Coates, et al. [65] Yes Yes No Yes No No Yes Yes Yes
McCarthy & McMahon [35] Yes Yes No No No No Yes Yes Yes
Yonker, et al. [14] Yes Yes No Yes Yes Yes Yes Yes Yes
Sharp, et al. [72] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Bloch, et al. [73] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Turner, et al. [36] Yes Yes Yes Yes Yes No Yes Yes Yes
O'Mahen, et al. [27] Yes Yes No No Yes Yes Yes Yes Yes
Reay, et al. [52] Yes Yes No Yes Yes Yes Yes Yes Yes
Morrell, et al. [45] Yes Yes Yes Yes Yes Yes Yes Yes Yes
Slade, et al. [49] Yes Yes No Yes Yes No Yes Yes Yes
Rojas, et al. [47] Yes Yes No Yes Yes Yes Yes Yes Yes
Honey, et al. [51] Yes Yes No No Yes No Yes Yes Yes
Broom, et al. [46] Yes Yes No No Yes No Yes Yes Yes
Klier, et al. [17] Yes Yes No No Yes Yes Yes No Yes
O'Hara, et al. [74] Yes Yes Yes Yes Yes Yes Yes Yes Yes