Table 2.
Characteristics of included studies and their quality appraisal results
|
Author, year, and country |
Study type |
No. & type of studies |
Outcomes measured |
Risk of bias measure |
Heterogeneity |
Prisma score |
Conclusions |
|
|
1 |
Corbella S et al.19 2013 (Italy) |
SR/MA |
15 total RCTs Only 8 NSPT vs no tx control Study range: 2001–2012 |
HbA1c FPG |
Cochrane Handbook Risk of bias: High (3) Low (5) |
Signif. I2 = 50% |
24/27 |
Baseline to 3 mos. HbA1c mean diff. (–0.38%) p = 0.01 Mean diff. at 6 mos. (–0.31%) p = 0.15 Authors’ conclusion: NSPT might be effective in metabolic control but significance is questionable & needs further investigation. |
|
2 |
Jain A et al.21 2019 (India) |
SR/MA |
6 RCTs NSPT vs no tx control Study range: 2011–2014 |
HbA1c |
Cochrane Handbook Risk of bias: High for detection & performance Unclear for selection bias |
Signif. I2 = 84% |
24/27 |
Baseline to 3 mos. HbA1c mean diff. (–0.26) but not statistically significant Authors’ conclusion: NSPT showed a modest trend in reducing HbA1c and should be included as part of the medical regime for patients with diabetes. |
|
3 |
Li Q, et al.22 2015 (China) |
MA |
9 RCTs Study range: 2005 (1) 2008 (1) 2012–2014 |
HbA1c |
Cochrane Handbook Risk of bias: High (3) Low (6) |
Moderate I2 = 41.7b |
23/27 |
Baseline to 3 mos. HbA1c mean diff. (pooled) (–0.27%) p = 0.0007 HbA1c mean diff. (large studies only) (–0.014%) p = 0.87 Authors’ conclusion: The moderate reduction in HbA1c after NSPT is consistent with previous SRs, however more large scale and higher quality studies are required. |
|
4 |
Sgolastra FG et al.23 2013 (Italy) |
MA |
5 RCTs Study range: 2005–2008 (2) 2012 (3) |
HbA1c |
Consort Risk of bias: High (3) Low (2) |
None I2 = 0% |
25/27 |
Baseline to 3 mos. HbA1c mean diff. 0.65% (p = 00001) Authors’ conclusion: Results seem to support improvements in glycemic control, however future studies needed to confirm results. |
|
5 |
Simpson TC et al.15 2015 (UK) |
Cochrane SR/MA |
35 RCTs (14 studies NSPT vs no tx) |
HbA1c |
Cochrane Handbook & Evidence Grade Risk of bias: High (29) Low (2) Unclear (4) GRADE Low |
Moderate I2 = 53% |
26/27 |
MAs for 14 studies (HbA1c after NSPT vs no tx) Largest # of participants (1499) compared to the other 4 reviews. Baseline to 3 mos. HbA1c mean diff. –0.29% (p = 0.003) Baseline to 6 mos. HbA1c mean diff. 0.02% Note: 2 subgroups (SRP [8] and SRP + antimicrobials [7]) No significant diff. between groups (p = 0.25) Authors’ conclusion: Low-quality evidence that SRP improves glycemic control in people with diabetes. |
|
6 |
Botero JE et al.24 2016 (Colombia) |
Umbrella review |
13 SR/MAs |
HbA1c |
PRISMA & AMSTAR high quality (8) moderate quality (5) Risk of bias: High or unclear for the majority of studies |
High (Range 0% to 89%) |
N/A |
Range in reduction of HbA1c for all studies was (0.23 to 1.03) Authors’ conclusion: Highly heterogenous studies with small sample sizes suggest NSPT could help improve glycemic control at 3 mos. |
|
7 |
Faggion CM et al.25 2016 (Germany) |
Umbrella review |
11 SR/MAs |
HbA1c |
AMSTAR & OQAQ Moderate quality (score range 5 to 9) |
High |
N/A |
Mean reduction of HbA1c for all studies was 0.47 (range 0.24 to 1.03) Authors’ conclusion: Findings do not support that NSPT improves glycemic control |
|
8 |
Hasuike A et al.26 2017 (Japan) |
Umbrella review |
13 MAs within 9 SRs |
HbA1c |
AMSTAR Not high quality |
High I2 > 40% |
N/A |
Range in reduction of HbA1c for all studies was (–0.93 to 0.13) Authors’ conclusion: Significant diff. but effect size small & studies not of high quality. |