Вот кстати, погуглил и нашел подтверждение того, к чему пришел интуитивно. Маленькая манжета увеличивает показания в большую сторону, и чем сильнее мала - тем больше врет.


https://www.heart.org/en/news/2022/03/01/when-it-comes-to-accurate-blood-pressure-readings-cuff-size-matters
They found using a cuff that was too small mistakenly resulted in higher blood pressure readings in 39% of participants, while using a cuff that was too large missed 22% of those who did have hypertension.
More than 40% of participants were classified as obese. Those who required a large or extra-large cuff had significantly higher readings when using a regular-sized cuff. Systolic readings were 4.8 mmHg higher for those needing a large cuff and 19.7 mmHg higher for those needing an extra-large.


А вообще вот хороший девайс. Но у нас недоступен.

https://aktiia.com/