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. 2019 Apr;11(2):159–167. doi: 10.4300/JGME-D-18-00746.1

Table 4.

Welch Statistic and Adjusted Alpha Value for Comparisons Among Groups With Unequal Variances by Frequency, Preparation, and Importance of Procedures

Frequency Region N Mean SD Welch Statistic df P esa
Emergent procedures Urban 169 20.7 2.26 13.26 2/64 ≤ .001b 0.852
Suburban 47 25.5 10.05
Rural 49 27.5 11.76
Urgent procedures Urban 169 29.8 10.70 2.63 2/104 .07 N/A
Suburban 47 32.9 8.01
Rural 49 31.6 8.33
Office-based procedures Urban 169 28.4 7.93 8.63 2/81 ≤ .001c 0.731
Suburban 47 31.9 9.31
Rural 49 34.9 11.63
Preparation Region N Mean SD Welch Statistic df P esa
Emergent procedures Urban 168 88.43 12.91 3.92 2/94 .023c 0.412
Suburban 47 89.60 13.19
Rural 47 93.38 10.01
Urgent procedures Urban 169 76.94 13.78 4.10 2/95 .020d 0.426
Suburban 47 76.17 12.57
Rural 49 82.45 12.45
Office-based procedures Urban 169 73.25 16.22 3.40 2/88 .038e 0.531
Suburban 47 69.50 16.61
Rural 49 78.64 17.79
Importance Region N Mean SD Welch Statistic df P esa
Emergent procedures Urban 169 67.42 18.19 17.05 2/89 ≤ .001d 0.831
Suburban 47 69.22 21.65
Rural 48 83.19 16.10
Urgent procedures Urban 169 71.13 15.82 3.17 2/94 .047 N/A
Suburban 47 70.72 12.79
Rural 48 77.42 16.16
Office-based procedures Urban 169 65.27 16.06 5.36 2/93 .006d 0.526
Suburban 47 65.87 14.56
Rural 49 73.71 16.06
a

Cohen's d effect size for paired comparisons of the significantly different groups using weighted means and pooled standard deviations when needed.

b

Games-Howell post-hoc tests indicate that the urban group's mean is significantly lower than the means of both the suburban and rural groups.

c

Games-Howell post-hoc tests indicate that the urban group's mean is significantly lower than the mean of the rural group only.

d

Games-Howell post-hoc tests indicate that the urban and suburban groups' means is significantly lower than the mean of the rural group.

e

Games-Howell post-hoc tests indicate that the suburban group mean is significantly lower than the mean of the rural group only.

Abbreviations: es, effect size; N/A, not available.