Summary of findings 5. Growth hormone (0.23 mg/kg/week for DMD and 0.07 mg/kg/week in BMD SC injection) versus placebo for DMD and BMD.

Growth hormone (0.23 mg/kg/week for DMD and 0.07/kg/week in BMD SC injection) versus placebo for DMD and BMD
Patient or population: people with DMD or BMD (ages not stated) Setting: Cardiomyology and Myology Centre of Naples Second University Intervention: growth hormone (0.23 mg/kg/week for DMD and 0.07 mg/kg/week in BMD subcutaneous injection) Comparison: placebo
Outcomes	Anticipated absolute effects* (95% CI)		Number of participants (studies)	Certainty of the evidence (GRADE)
	Risk with placebo	Risk with growth hormone
Change in cardiac function: ejection fraction assessed with: echocardiography Follow‐up: 3 months	Outcomes were reported at 3 months. No between‐group comparisons of echocardiographic indices for the DMD group (N = 6) were performed due to the small sample size; LV mass index, end‐systolic stress and ejection fraction results were presented graphically The study authors report a non‐significant trend for increase in LV fractional shortening in growth‐hormone‐treated DMD participants.		16 (1 RCT)	⊕⊝⊝⊝ Very lowa,b,c
Size of metabolically abnormal areas of myocardium	Not reported
Improvements in quality of life measures	Not reported
Adverse events	None reported		16 (1 RCT)	⊕⊝⊝⊝ Very lowa,b,c
*The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). BMD: Becker muscular dystrophy; CI: confidence interval; DMD: Duchenne muscular dystrophy; LV: left ventricular; RCT: randomised controlled trial; RR: risk ratio.
GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

^aDowngraded twice for study limitations: inadequate randomisation, confounding from concomitant medications, and selective reporting (numerical results not provided).
 ^bDowngraded for imprecision (N = 16).
 ^cDowngraded once for indirectness: trial duration 3 months rather than the 6 months specified for this review.