A Boswellia trial reports a benefit and does not report how large

Design

randomised, double-blind, placebo-controlled trial over 8 weeks

Population

60 adults aged 40 to 75 with mild to moderate knee osteoarthritis

Primary outcome

total WOMAC score and subscales, visual analogue scale, at days 7, 15, 30 and 60

Effect

significant reduction in total WOMAC, pain, stiffness and visual analogue scores and in hs-CRP versus placebo, reported only as P < .05 with no effect sizes given

Sixty adults aged 40 to 75 with mild to moderate knee osteoarthritis were randomised, double-blind, to 100 mg once daily of a standardised Boswellia serrata extract or placebo for eight weeks, with WOMAC total and subscale scores and a visual analogue scale measured at days 7, 15, 30 and 60.

The extract reduced total WOMAC, pain, stiffness and visual analogue scores and improved physical function against placebo, all reported only as P < .05. High-sensitivity CRP fell significantly compared with placebo. Separation on pain and stiffness was reported as early as day 7. It was described as safe and well tolerated.

What is missing is the part a clinician needs. No mean differences, no confidence intervals, no minimal clinically important difference — so there is no way to tell whether this is a WOMAC change a patient would notice or one only a statistical test can. Boswellia is widely used in India and widely sold, and the question patients ask is exactly the one this trial does not answer. It is a signal in a small, short study of a single proprietary extract, and should be described to patients that way.

• If a patient is already taking Boswellia, there is no safety reason to stop it
• Do not present this as equivalent to established osteoarthritis management
• Ask which preparation — the evidence attaches to specific standardised extracts, not to the herb generally
• Continue exercise, weight management and analgesia as the core of treatment
• Be clear that no effect size was published, so the size of any benefit is unknown

Why it matters

This is the supplement Indian patients are most likely to already be taking, and the evidence is usually quoted without its limits.

Don't overread it

A single small industry-relevant trial of one proprietary extract over eight weeks, with no effect sizes reported.

The statistics, in plain English

A result reported only as P < .05 tells you the difference was unlikely to be chance in these 60 people, and nothing about whether it was big enough to matter. With 30 per arm, the trial is also underpowered to detect anything about safety beyond the obvious.

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