The Study
Misclassification Bias in the Waist‐To‐Hip Ratio: Implications for Obesity‐Related Risk of Incident Type 2 Diabetes
This study looked at a bunch of older Chinese adults over several years and noticed that people with big waists and big hips were more likely to get diabetes, even if their waist-to-hip ratio looked normal. It didn’t make anyone change their body — it just watched what happened, so we can’t say changing your body shape will stop diabetes — only that these measurements are connected.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
Even if your waist-to-hip ratio looks normal, if you have a big waist and big hips, you might still be at high risk for diabetes — because the actual size of your waist matters more than the ratio.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 567 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — this means someone with a 'healthy' waist-to-hip ratio could still be at high risk if they have a large waist, and doctors should check both waist size and BMI, not just the ratio.
- 2People with big waist and big hips had 73% to 133% higher diabetes risk than those with small waist and hips, even with the same waist-to-hip ratio.
- 3Adding BMI to waist-to-hip ratio improved diabetes prediction accuracy by 2.8% (C-statistic increase).
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
International Journal of Endocrinology
Year
2026
Authors
Si-Han Hou, Jiao Wang, T. Lam, Lin Yang, W. Zhang, Lin Xu
Related Content
Claims (6)
People with a higher waist-to-hip ratio have a higher rate of metabolic and cardiovascular disease.
Using both waist-to-hip ratio and body mass index together predicts type 2 diabetes risk more accurately in adults aged 50 and older than using waist-to-hip ratio alone, as measured by a 0.028 increase in the C-statistic and better reclassification of risk categories.
Adults aged 50 and older with larger waist and hip measurements have a higher risk of developing type 2 diabetes, even if their waist-to-hip ratio is low or high.
Among adults aged 50 and older, people with both a large waist and large hips have a 73% to 133% higher risk of developing type 2 diabetes than people with small waist and hip measurements, even when their waist-to-hip ratio is the same.
In adults aged 50 and older, waist circumference and waist-to-height ratio are better at identifying who will develop type 2 diabetes than waist-to-hip ratio, based on their statistical performance metrics.
In adults aged 50 and older, using both waist-to-hip ratio and body mass index together identifies type 2 diabetes risk more accurately than using waist circumference and body mass index together, as measured by a statistically significant increase in the C-statistic of 0.007.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.