Cohort studycited by the Tayebat archiveabstract only checked★ key study A-ABX-01 in-depth review
Antibiotics in infancy and childhood obesity
Association of antibiotics in infancy with early childhood obesity.
Overview
Bailey LC et al.. JAMA Pediatr 2014 · PMID 25265089 · DOI 10.1001/jamapediatrics.2014.1539
Children with 4+ antibiotic courses before age 2 were about 11% more likely to be obese.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Link antibiotics to obesity.
- How was the study done?
Health-record cohort.
- How many people, animals or samples were studied?
64,580 children.
- What was actually found?
Small increased risk with broad-spectrum.
- How large was the observed effect?
RR 1.11-1.16.
- What do the results mean in everyday life?
Small effect, may not be causal.
- What are the study's limitations?
Observational.
- What does it say about Elawady's specific claim?
Supports association.
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
Causation.
Scientific in-depth review
1. Full reference
- Authors
- Bailey LC, Forrest CB, Zhang P, Richards TM, Livshits A, DeRusso PA
- Journal
- JAMA Pediatr
- Year
- 2014
- Identifier
- PMID 25265089 DOI 10.1001/jamapediatrics.2014.1539
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
not stated in abstract/record
2. Research question
Do antibiotics at 0-23 months affect obesity at 24-59 months?
3. Study design and population
- Study design
- Cohort study – Retrospective EHR cohort, Cox models
- Population
Children in CHOP primary-care network
- Country
USA (Philadelphia region)
- Period
2001-2013
- Sample size
64,580
- Inclusion and exclusion criteria
Annual visits 0-23 months and >=1 visit at 24-59 months
4. Methods and endpoints
- Exposure / intervention
Antibiotic episodes (number, spectrum, timing)
- Comparator
Fewer/no episodes
- Endpoints
Obesity (NHANES BMI norms)
- Statistical methods
Cox PH, adjusted for demographic, practice, clinical covariates
5. Actual results
- Results
69% exposed; >=4 episodes RR 1.11 (1.02-1.21); broad-spectrum RR 1.16 (1.06-1.29); broad-spectrum at 0-5 months RR 1.11 (1.03-1.19), 6-11 months RR 1.09 (1.04-1.14); narrow-spectrum not associated.
- Absolute risks
not reported
- Authors' conclusion
Repeated broad-spectrum exposure is associated with early childhood obesity; narrowing selection is potentially a modifiable risk factor.
6. Strengths
- Large
- Measured anthropometry
- Spectrum-specific analysis (narrow-spectrum null acts as partial negative control)
7. Weaknesses
- Observational; residual confounding
- Infections may confound
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Confounding by indication possible; narrow-spectrum null result reduces but does not exclude it.
9. Assessment of the statistical interpretation
Small relative effect (11-16%); absolute risk not reported in abstract.
10. Relevance to the specific claim
11. Independent contrary findings
I-ABX-04 (very low certainty).
12. Transferability to Germany and Europe
Moderate.
13. Overall methodological judgement
Good cohort; association.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | direct |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | essentially correct but incomplete |
14. Open questions
Causality.
15. Linked fact checks
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
In 64,580 children, >=4 courses of broad-spectrum antibiotics before age two raised early-childhood obesity risk by 11-16%.
- A. What was actually studied?
Antibiotics and obesity.
- B. What did the authors find?
RR 1.11 (>=4 episodes), 1.16 broad-spectrum.
- C. What conclusions do the authors themselves draw?
Associated; narrowing spectrum potentially modifiable.
- D. What does the archive derive from it?
'Raised risk' (causal wording).
- E. Is this derivation scientifically justified?
Numbers correct; causal phrasing ('raised') overstates an association. Note: RR 1.11 is for >=4 episodes of any antibiotic; 1.16 is the broad-spectrum estimate.
- Adequacy of the interpretation (by the archive)
- essentially correct but incomplete