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Cochrane Database of Systematic Reviews

Probióticos para la prevención de infecciones agudas de las vías respiratorias superiores

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DOI:
https://doi.org/10.1002/14651858.CD006895.pub3Copy DOI
Database:
  1. Cochrane Database of Systematic Reviews
Version published:
  1. 03 February 2015see what's new
Type:
  1. Intervention
Stage:
  1. Review
Cochrane Editorial Group:
  1. Cochrane Acute Respiratory Infections Group

Copyright:
  1. Copyright © 2015 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

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Authors

  • Qiukui Hao

    Center of Geriatrics and Gerontology, West China Hospital, Sichuan University, Chengdu, China

  • Bi Rong Dong

    Correspondence to: Center of Geriatrics and Gerontology, West China Hospital, Sichuan University, Chengdu, China

    [email protected]

  • Taixiang Wu

    Chinese Clinical Trial Registry, Chinese Ethics Committee of Registering Clinical Trials, West China Hospital, Sichuan University, Chengdu, China

Contributions of authors

Qiukui Hao (QH) searched for trials, assessed the quality of trials, extracted data, analysed data and drafted the review.
Bi Rong Dong (BD) advised and assisted in writing the protocol and the review, searched for trials and developed the review.
Taixiang Wu (TW) contributed to the development of the methods of the review and assisted with data extraction and analysis.

Sources of support

Internal sources

  • Chinese Cochrane Center, West China Hospital of Sichuan University, China.

External sources

  • Editorial base and team of the Cochrane ARI Group, Australia.

Declarations of interest

Qiukui Hao: none known.
Bi Rong Dong: none known.
Taixiang Wu: none known.

Acknowledgements

The authors wish to thank Liz Dooley (Managing Editor) of the Cochrane Acute Respiratory Infections (ARI) Group, Janet Wale, Ann Fonfa, Shilpa Amin, Iva Hojsak, Simone Guglielmetti, Michael de Vrese, Karin Stockert, Nelcy Rodriguez, Teresa Neeman, Roger Damoiseaux and the Chinese Cochrane Center for commenting on drafts of this review. The authors also want to thank Dr. Zhenchan Lu and Dr. Changquan Huang for their co‐authoring contributions to the previous version of this review.

Version history

Published

Title

Stage

Authors

Version

2022 Aug 24

Probiotics for preventing acute upper respiratory tract infections

Review

Yunli Zhao, Bi Rong Dong, Qiukui Hao

https://doi.org/10.1002/14651858.CD006895.pub4

2015 Feb 03

Probiotics for preventing acute upper respiratory tract infections

Review

Qiukui Hao, Bi Rong Dong, Taixiang Wu

https://doi.org/10.1002/14651858.CD006895.pub3

2011 Sep 07

Probiotics for preventing acute upper respiratory tract infections

Review

Qiukui Hao, Zhenchan Lu, Bi Rong Dong, Chang Quan Huang, Taixiang Wu

https://doi.org/10.1002/14651858.CD006895.pub2

2008 Jan 23

Probiotics for preventing acute upper respiratory tract infections

Protocol

Zhenchan Lu, Bi Rong Dong, Chang Quan Huang, Taixiang Wu

https://doi.org/10.1002/14651858.CD006895

Differences between protocol and review

We have replaced the 'Quality assessment of included studies' in the original version with 'Assessment of risk of bias in included studies' and the methods of analysis according to the new version of the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We also revised the outcomes and used GRADE to assess the overall quality of the evidence following the instructions in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We did not include all respiratory tract infections because many studies just reported the respiratory tract infection rather than specifying whether it was a lower or upper respiratory traction infection, which may increase the levels of clinical heterogeneity.

Notes

In the next update of this review, we will include a subgroup to assess the effects of prebiotics on acute respiratory tract infections.

Keywords

MeSH

Medical Subject Headings Check Words

Adult; Aged; Child; Female; Humans; Male;

PICOs

Population
Intervention
Comparison
Outcome

The PICO model is widely used and taught in evidence-based health care as a strategy for formulating questions and search strategies and for characterizing clinical studies or meta-analyses. PICO stands for four different potential components of a clinical question: Patient, Population or Problem; Intervention; Comparison; Outcome.

See more on using PICO in the Cochrane Handbook.

Chinese Biomedical Literature Database search strategy.
Figures and Tables -
Figure 1

Chinese Biomedical Literature Database search strategy.

Study flow diagram.
Figures and Tables -
Figure 2

Study flow diagram.

'Risk of bias' graph: review authors' judgements about each methodological quality item presented as percentages across all included studies.
Figures and Tables -
Figure 3

'Risk of bias' graph: review authors' judgements about each methodological quality item presented as percentages across all included studies.

'Risk of bias' summary: review authors' judgements about each risk of bias item for each included study.
Figures and Tables -
Figure 4

'Risk of bias' summary: review authors' judgements about each risk of bias item for each included study.

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 1 The number of participants who experienced URTI episodes: at least 1 event.
Figures and Tables -
Analysis 1.1

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 1 The number of participants who experienced URTI episodes: at least 1 event.

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 2 The number of participants who experienced URTI episodes: at least 3 events.
Figures and Tables -
Analysis 1.2

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 2 The number of participants who experienced URTI episodes: at least 3 events.

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 3 The rate ratio of episodes of acute URTI.
Figures and Tables -
Analysis 1.3

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 3 The rate ratio of episodes of acute URTI.

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 4 The mean duration of an episode of URTI.
Figures and Tables -
Analysis 1.4

Comparison 1 ITT analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 4 The mean duration of an episode of URTI.

Comparison 2 ITT analysis: probiotics versus placebo ‐ time off from childcare centre, school or work, Outcome 1 The number of participants who were absent due to URTIs.
Figures and Tables -
Analysis 2.1

Comparison 2 ITT analysis: probiotics versus placebo ‐ time off from childcare centre, school or work, Outcome 1 The number of participants who were absent due to URTIs.

Comparison 3 ITT analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs, Outcome 1 The number of participants who used antibiotics.
Figures and Tables -
Analysis 3.1

Comparison 3 ITT analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs, Outcome 1 The number of participants who used antibiotics.

Comparison 4 ITT analysis: probiotics versus placebo ‐ side effects or adverse events, Outcome 1 The number of side effects.
Figures and Tables -
Analysis 4.1

Comparison 4 ITT analysis: probiotics versus placebo ‐ side effects or adverse events, Outcome 1 The number of side effects.

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 1 Number of participants who experienced URTI episodes: at least 1 event.
Figures and Tables -
Analysis 5.1

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 1 Number of participants who experienced URTI episodes: at least 1 event.

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 2 Number of participants who experienced URTI episodes: at least 3 events.
Figures and Tables -
Analysis 5.2

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 2 Number of participants who experienced URTI episodes: at least 3 events.

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 3 The rate ratio of episodes of acute URTI.
Figures and Tables -
Analysis 5.3

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 3 The rate ratio of episodes of acute URTI.

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 4 The mean duration of an episode of URTI.
Figures and Tables -
Analysis 5.4

Comparison 5 Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures, Outcome 4 The mean duration of an episode of URTI.

Comparison 6 Per‐protocol analysis: probiotics versus placebo ‐ time off from childcare centre, school or work, Outcome 1 The number of participants who experienced school absence due to URTIs.
Figures and Tables -
Analysis 6.1

Comparison 6 Per‐protocol analysis: probiotics versus placebo ‐ time off from childcare centre, school or work, Outcome 1 The number of participants who experienced school absence due to URTIs.

Comparison 7 Per‐protocol analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs, Outcome 1 The number of participants who used antibiotics.
Figures and Tables -
Analysis 7.1

Comparison 7 Per‐protocol analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs, Outcome 1 The number of participants who used antibiotics.

Comparison 8 Per‐protocol analysis: probiotics versus placebo ‐ side effects or adverse events, Outcome 1 The number of side effects.
Figures and Tables -
Analysis 8.1

Comparison 8 Per‐protocol analysis: probiotics versus placebo ‐ side effects or adverse events, Outcome 1 The number of side effects.

Summary of findings for the main comparison. Probiotics for preventing acute upper respiratory tract infections: primary outcomes

Probiotics for preventing acute upper respiratory tract infections: primary outcomes

Patient or population: adults, children and the elderly
Settings: community or care facilities or school or hospital
Intervention: probiotics

Outcomes

Illustrative comparative risks* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Control

ITT analysis: probiotics versus placebo ‐ primary outcome measures

The number of participants who experienced URTI episodes: at least 1 event

Study population

OR 0.53
(0.37 to 0.76)

1927
(7 trials)

⊕⊕⊝⊝
low1,2

2 of 7 trials were at risk of high bias due to funding by related companies (Berggren 2010; Sanz 2006)

306 per 1000

189 per 1000
(140 to 251)

Moderate

421 per 1000

278 per 1000
(212 to 356)

The number of participants who experienced URTI episodes: at least 3 events

Study population

OR 0.53
(0.36 to 0.8)

650
(3 trials)

⊕⊕⊝⊝
low1,2

All 3 trials were unclear for sequence generation and allocation concealment (Berggren 2010; Rautava 2009; Sanz 2006) and 2 of them were at high risk of bias due to funding by related companies (Berggren 2010; Sanz 2006)

293 per 1000

180 per 1000
(130 to 249)

Moderate

233 per 1000

139 per 1000
(99 to 196)

The risk ratio of episodes of acute URTI

Study population

Rate ratio 0.83
(0.66 to 1.05)

1608
(5 trials)

⊕⊝⊝⊝
very low1,2,3

2 trials had serious limitations: Berggren 2010 was unclear for sequence generation and allocation concealment; Rio 2002 had a high proportion of incomplete data. 2 of 5 trials were at high risk of bias due to funding by related companies (Berggren 2010; Caceres 2010). Serious inconsistency: I2 statistic was 76%

See comment

See comment

Moderate

0 per 1000

0 per 1000
(0 to 0)

The mean duration of an episode of URTIs

The mean duration of an episode of URTI in the intervention groups was
1.89 lower
(2.03 to 1.75 lower)

831
(3 trials)

⊕⊕⊝⊝
Low1,3

1 of the 3 trials was unclear for sequence generation and allocation concealment (Vrese 2005)

*The basis for the assumed risk (e.g. the median control group risk across trials) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; OR: odds ratio;URTI: upper respiratory tract infection

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1One or more items for the bias assessment in included trials were unclear. Downgraded by 1.
2Serious study limitations: some trials were at high risk of bias due to funding by manufacturers of the tested probiotics. Downgraded by 1.
3Serious inconsistency: small sample size or have a higher I2, or both. Downgraded by 1.

Figures and Tables -
Summary of findings for the main comparison. Probiotics for preventing acute upper respiratory tract infections: primary outcomes
Summary of findings 2. Probiotics for preventing acute upper respiratory tract infections: time off from childcare centre, school or work

Probiotics for preventing acute upper respiratory tract infections: school absence due to URTIs

Patient or population: children
Settings: school
Intervention: probiotics

Outcomes

Illustrative comparative risks* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Control

Probiotics

Time off from childcare centre, school or work

Study population

OR 0.10
(0.02 to 0.47)

80
(1 study)

⊕⊝⊝⊝
very low1,2

The study was unclear for randomised sequence generation and allocation concealment and only 80 participants were included (Rerksuppaphol 2012)

350 per 1000

51 per 1000
(11 to 202)

Moderate

350 per 1000

51 per 1000
(11 to 202)

*The basis for the assumed risk (e.g. the median control group risk across trials) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; OR: odds ratio; URTI: upper respiratory tract infection

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1Some items for the bias assessment were unclear. Downgraded by 1.
2Very small events and wide 95% CI range in this analysis. Downgraded by 2.

Figures and Tables -
Summary of findings 2. Probiotics for preventing acute upper respiratory tract infections: time off from childcare centre, school or work
Summary of findings 3. Probiotics for preventing acute upper respiratory tract infections: prescribed antibiotics for acute URTIs

Probiotics for preventing acute upper respiratory tract infections: antibiotics usage

Patient or population: children
Settings: school or care facilities or hospital
Intervention: probiotics

Outcomes

Illustrative comparative risks* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Control

Probiotics

Prescribed antibiotics for acute URTIs

Study population

RR 0.65
(0.45 to 0.94)

1184
(4 trials)

⊕⊕⊕⊝
moderate1

Unclear randomised sequence generation and allocation concealment in all 4 trials (Hojsak 2010a; Hojsak 2010b; Rautava 2009; Rerksuppaphol 2012)

98 per 1000

64 per 1000
(44 to 92)

Moderate

179 per 1000

116 per 1000
(81 to 168)

*The basis for the assumed risk (e.g. the median control group risk across trials) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; RR: risk ratio; URTI: upper respiratory tract infection

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1Some items for the bias assessment were unclear. Downgraded by 1.

Figures and Tables -
Summary of findings 3. Probiotics for preventing acute upper respiratory tract infections: prescribed antibiotics for acute URTIs
Summary of findings 4. Probiotics for preventing acute upper respiratory tract infections: side effects or adverse events

Probiotics for preventing acute upper respiratory tract infections: adverse events

Patient or population: adults or children
Settings: community or school
Intervention: probiotics

Outcomes

Illustrative comparative risks* (95% CI)

Relative effect
(95% CI)

No. of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

Control

Probiotics

Side effects or adverse events

Study population

OR 0.88
(0.65 to 1.19)

1234
(4 trials)

⊕⊕⊝⊝
low1,2

3 of 4 trials were unclear for randomised sequence generation and allocation concealment (Berggren 2010; Rerksuppaphol 2012; Smith 2013)

89 per 1000

79 per 1000
(51 to 120)

Moderate

114 per 1000

102 per 1000
(66 to 153)

*The basis for the assumed risk (e.g. the median control group risk across trials) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; OR: odds ratio

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1Some items for the bias assessment were unclear. Downgraded by 1.
2The sample size was small and the 95% CI crossed 1. Downgraded by 1.

Figures and Tables -
Summary of findings 4. Probiotics for preventing acute upper respiratory tract infections: side effects or adverse events
Comparison 1. ITT analysis: probiotics versus placebo ‐ primary outcome measures

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of participants who experienced URTI episodes: at least 1 event Show forest plot

7

1927

Odds Ratio (IV, Random, 95% CI)

0.53 [0.37, 0.76]

1.1 Adults

1

318

Odds Ratio (IV, Random, 95% CI)

0.68 [0.44, 1.06]

1.2 Children

5

1457

Odds Ratio (IV, Random, 95% CI)

0.43 [0.29, 0.63]

1.3 Elderly

1

152

Odds Ratio (IV, Random, 95% CI)

0.95 [0.50, 1.81]

2 The number of participants who experienced URTI episodes: at least 3 events Show forest plot

3

650

Odds Ratio (IV, Random, 95% CI)

0.53 [0.36, 0.80]

2.1 Adults

1

318

Odds Ratio (IV, Random, 95% CI)

0.47 [0.21, 1.03]

2.2 Children

2

332

Odds Ratio (IV, Random, 95% CI)

0.56 [0.35, 0.89]

3 The rate ratio of episodes of acute URTI Show forest plot

5

1608

Rate Ratio (Random, 95% CI)

0.83 [0.66, 1.05]

3.1 Adults

1

318

Rate Ratio (Random, 95% CI)

0.71 [0.56, 0.90]

3.2 Children

3

1136

Rate Ratio (Random, 95% CI)

0.77 [0.57, 1.05]

3.3 Elderly

1

154

Rate Ratio (Random, 95% CI)

1.37 [0.94, 1.99]

4 The mean duration of an episode of URTI Show forest plot

3

831

Mean Difference (IV, Random, 95% CI)

‐1.89 [‐2.03, ‐1.75]

4.1 Adults

2

677

Mean Difference (IV, Random, 95% CI)

‐1.90 [‐2.04, ‐1.76]

4.2 Elderly

1

154

Mean Difference (IV, Random, 95% CI)

‐1.69 [‐2.75, ‐0.63]

Figures and Tables -
Comparison 1. ITT analysis: probiotics versus placebo ‐ primary outcome measures
Comparison 2. ITT analysis: probiotics versus placebo ‐ time off from childcare centre, school or work

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of participants who were absent due to URTIs Show forest plot

1

Odds Ratio (M‐H, Random, 95% CI)

Totals not selected

Figures and Tables -
Comparison 2. ITT analysis: probiotics versus placebo ‐ time off from childcare centre, school or work
Comparison 3. ITT analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of participants who used antibiotics Show forest plot

4

1184

Risk Ratio (M‐H, Random, 95% CI)

0.65 [0.45, 0.94]

Figures and Tables -
Comparison 3. ITT analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs
Comparison 4. ITT analysis: probiotics versus placebo ‐ side effects or adverse events

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of side effects Show forest plot

4

1234

Risk Ratio (M‐H, Random, 95% CI)

0.88 [0.65, 1.19]

1.1 Adults

2

516

Risk Ratio (M‐H, Random, 95% CI)

1.09 [0.66, 1.81]

1.2 Children

2

718

Risk Ratio (M‐H, Random, 95% CI)

0.77 [0.53, 1.13]

Figures and Tables -
Comparison 4. ITT analysis: probiotics versus placebo ‐ side effects or adverse events
Comparison 5. Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Number of participants who experienced URTI episodes: at least 1 event Show forest plot

7

1760

Odds Ratio (IV, Random, 95% CI)

0.51 [0.34, 0.77]

1.1 Adults

1

275

Odds Ratio (IV, Random, 95% CI)

0.60 [0.37, 0.97]

1.2 Children

5

1351

Odds Ratio (IV, Random, 95% CI)

0.41 [0.25, 0.69]

1.3 Elderly

1

134

Odds Ratio (IV, Random, 95% CI)

1.00 [0.51, 1.96]

2 Number of participants who experienced URTI episodes: at least 3 events Show forest plot

3

582

Odds Ratio (IV, Random, 95% CI)

0.56 [0.37, 0.84]

2.1 Adults

1

275

Odds Ratio (IV, Random, 95% CI)

0.45 [0.20, 1.00]

2.2 Children

2

307

Odds Ratio (IV, Random, 95% CI)

0.60 [0.37, 0.98]

3 The rate ratio of episodes of acute URTI Show forest plot

5

1380

Rate Ratio (Random, 95% CI)

0.91 [0.71, 1.16]

3.1 Adults

1

275

Rate Ratio (Random, 95% CI)

0.70 [0.55, 0.89]

3.2 Children

3

971

Rate Ratio (Random, 95% CI)

0.89 [0.64, 1.23]

3.3 Elderly

1

134

Rate Ratio (Random, 95% CI)

1.37 [0.94, 1.99]

4 The mean duration of an episode of URTI Show forest plot

3

768

Mean Difference (IV, Random, 95% CI)

‐1.89 [‐2.04, ‐1.75]

4.1 Adults

2

634

Mean Difference (IV, Random, 95% CI)

‐1.90 [‐2.04, ‐1.75]

4.2 Elderly

1

134

Mean Difference (IV, Random, 95% CI)

‐1.69 [‐2.83, ‐0.55]

Figures and Tables -
Comparison 5. Per‐protocol analysis: probiotics versus placebo ‐ primary outcome measures
Comparison 6. Per‐protocol analysis: probiotics versus placebo ‐ time off from childcare centre, school or work

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of participants who experienced school absence due to URTIs Show forest plot

1

Risk Ratio (M‐H, Random, 95% CI)

Totals not selected

Figures and Tables -
Comparison 6. Per‐protocol analysis: probiotics versus placebo ‐ time off from childcare centre, school or work
Comparison 7. Per‐protocol analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of participants who used antibiotics Show forest plot

4

1122

Risk Ratio (M‐H, Random, 95% CI)

0.65 [0.45, 0.94]

Figures and Tables -
Comparison 7. Per‐protocol analysis: probiotics versus placebo ‐ prescribed antibiotics for acute URTIs
Comparison 8. Per‐protocol analysis: probiotics versus placebo ‐ side effects or adverse events

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 The number of side effects Show forest plot

4

1095

Risk Ratio (M‐H, Random, 95% CI)

0.80 [0.57, 1.12]

1.1 Adults

2

455

Risk Ratio (M‐H, Random, 95% CI)

1.01 [0.44, 2.31]

1.2 Children

2

640

Risk Ratio (M‐H, Random, 95% CI)

0.76 [0.53, 1.10]

Figures and Tables -
Comparison 8. Per‐protocol analysis: probiotics versus placebo ‐ side effects or adverse events