A visual walking questionnaire originally designed for people with little or no schooling could help spot dangerously low haemoglobin levels in pregnant women, new research suggests. The Walking Estimated Limitation Stated by History (WELSH) tool asks women to choose pictures that best reflect how far they can walk, providing a simple measure of functional walking ability.
Study links WELSH scores to haemoglobin
Researchers carried out a prospective study in pregnant women admitted to hospital with documented severe anaemia. Each woman completed the WELSH questionnaire on admission and again at discharge after receiving a blood transfusion. The team then compared WELSH scores with laboratory haemoglobin (Hb) values, calculating how closely the two measures moved together.
The coefficient of determination between Hb and WELSH was 0.35 at admission and 0.5 at discharge, indicating a moderate correlation at each time point. When all measurements were combined, the overall R² rose to 0.83, showing a strong relationship between changes in WELSH score and changes in haemoglobin.
Strong performance in detecting very low Hb
The WELSH tool also performed well in identifying women with particularly severe anaemia. The area under the ROC curve for predicting Hb below 7 g/dl was 0.98 with a small standard deviation, a level usually interpreted as excellent diagnostic accuracy. In practical terms, this means a low WELSH score was highly predictive of critically low haemoglobin.
Potential lifeline for low-resource settings
The authors conclude that WELSH is both sensitive to and correlated with haemoglobin changes in severe anaemia of pregnancy. Because it relies on pictures rather than text or numbers, it may be especially valuable in low-income settings, where many women have limited schooling and access to laboratory testing is scarce. Used in community or primary care, the tool could help frontline workers decide which women need urgent referral for blood testing and possible transfusion, potentially reducing maternal and fetal risks linked to untreated severe anaemia.
Reference
Ouédraogo N et al. The WELSH tool, is valid and sensitive to changes during the assessment of walking ability in severe anemia of pregnancy. Scientific Reports. 2025;15:42421.
