Table 4.

Comparison of Relative Risk (RR) and Number needed to treat (NNT) between the two groups based on study outcomes in participants (n = 54)

Outcome a	ESWT (n = 27)	Corticosteroid TPI (n = 27)	P value†	RR (95% CI)	NNT (95% CI)
ODI	17 (63.0%)	4 (14.8%)	< 0.001	2.67 (1.53 to 4.66)	2 (1.35 to 3.61)
PPT	23 (85.20%)	18 (66.70%)	0.111	1.82 (0.84 to 2.18)	5.4 (2.54 to 22.4)
SF-36	10 (37.0%)	1 (3.7%)	0.002	2.30 (1.62 to 43.26)	2 (1.35 to 3.45)
VAS	16 (59.3%)	7 (25.9%)	0.013	1.46 (1.04 to 2.19)	3 (1.85 to 14.4)

Note: The data are presented as frequency (percentage)

Abbreviations: ESWT Extracorporeal shockwave, TPI Trigger point injection, RR Relative risk, NNT Number Needed to Treat, CI confidence interval (calculated using exact method), ODI Oswestry disability index, PPT Pressure Pain Threshold, SF-36 Short Form (36) Health Survey; VAS: Visual Analogue Scale

Symbols: ^aThe outcomes is defined as at least 30% reduction in the final score (after 4 weeks) of VAS compared with the baseline score, OR at least 30% reduction in the final score (after 4 weeks) of ODI compared with the baseline score, OR a mean difference of 0.94 kg/cm² (after 4 weeks) of PPT compared with the baseline score, OR at least 20% increase in the final score (after 4 weeks) of SF-36 compared with the baseline score; †obtained from χ² Chi-Square test or Fisher’s exact test