Sample   Test (n=5) Method 3D 4D 1DD HPLC Carvedilol (CARV) (245.9 nm) (247.4 nm) (236.1 nm)   Bulk power Mean ± RSD (%) 100.39 ± 0.93 100.27 ± 0.77 100.50 ± 0.81 100.90 ± 0.69a t 0.98 1.36 0.84 (2.306)d F 1.82 1.25 1.38 (6.39)d Dilatrend tablets Mean ± RSD (%) 99.85 ± 0.62 99.93 ± 0.63 99.90 ± 0.51 99.66 ± 0.72 a t 0.42 0.40 0.60   F 1.37 1.30 2.07   Co-dilatrol tablets Mean ± RSD (%) 99.91 ± 0.51 99.96 ± 0.48 99.93 ± 0.53 99.89 ± 0.70b t 0.05 0.18 0.18   F 1.88 2.13 1.74   Hydrochlorothiazide (HCT) (230.2 nm) (226.9 nm) (261.1 nm)   Bulk power Mean±RSD(%) 99.85 ± 0.70 100.28 ± 0.94 100.57 ± 0.84 99.93 ± 0.68c   t 0.18 0.67 1.32   F 1.06 1.91 1.53   Co-dilatrol Mean ± RSD (%) 99.90 ± 0.72 99.85 ± 0.61 99.97 ± 0.80 99.72 ± 0.96b tablets t 0.34 0.26 0.45   F 1.77 2.49 1.44   a Reference no. [13]. b Reference no. [5]. c The United States Pharmacopoeia 2009 [14]. d Theoretical values of t- and F- tests at 95% confidence level.

Table 4: Results of the determination of CARV and HTC using 3D, 4D, 1DD and HPLC methods in bulk power and in commercial tablets.