Introduction The use of activity trackers has increased both among private consumers and in healthcare. It is therefore relevant to consider whether a consumer-graded activity tracker is comparable to or may substitute a research-graded activity tracker, which could further increase the use of activity trackers in healthcare and rehabilitation. Such use will require knowledge of their accuracy as the clinical implications may be significant. Studies have indicated that activity trackers are not sufficiently accurate, especially at lower walking speeds. The present study seeks to inform decision makers and healthcare personnel considering implementing physical activity trackers in clinical practice. This study investigates the criterion validity of the consumer-graded Garmin Vivosmart® HR and the research-graded StepWatch™ 3 compared with manual step count (gold standard) at different walking speeds under controlled conditions. Methods Thirty participants, wearing Garmin Vivosmart® HR at the wrist and StepWatch™ 3 at the ankle, completed six trials on a treadmill at different walking speeds: 1.6 km/h, 2.4 km/h, 3.2 km/h, 4.0 km/h, 4.8 km/h, and 5.6 km/h. The participants were video recorded, and steps were registered by manual step count. Medians and inter-quartile ranges (IQR) were calculated for steps and differences in steps between manually counted steps and the two devices. In order to assess the clinical relevance of the tested devices, the mean absolute percentage error (MAPE) was determined at each speed. A MAPE ≤3% was considered to be clinically irrelevant. Furthermore, differences between manually counted steps and steps recorded by the two devices were presented in Bland–Altman style plots. Results The median of differences in steps between Garmin Vivosmart® HR and manual step count ranged from −49.5 (IQR = 101) at 1.6 km/h to −1 (IQR = 4) at 4.0 km/h. The median of differences in steps between StepWatch™ 3 and manual step count were 4 (IQR = 14) at 1.6 km/h and 0 (IQR = 1) at all other walking speeds. The results of the MAPE showed that differences in steps counted by Garmin Vivosmart® HR were clinically irrelevant at walking speeds 3.2–4.8 km/h (MAPE: 0.61–1.27%) as the values were below 3%. Differences in steps counted by StepWatch™ 3 were clinically irrelevant at walking speeds 2.4–5.6 km/h (MAPE: 0.08–0.35%). Conclusion Garmin Vivosmart® HR tended to undercount steps compared with the manual step count, and StepWatch™ 3 slightly overcounted steps compared with the manual step count. Both the consumer-graded activity tracker (Garmin Vivosmart® HR) and the research-graded (StepWatch™ 3) are valid in detecting steps at selected walking speeds in healthy adults under controlled conditions. However, both activity trackers miscount steps at slow walking speeds, and the consumer graded activity tracker also miscounts steps at fast walking speeds.

In 652 young female diabetics the ABO and Rhesus type distribution did not differ significantly from that of the control series. Subdivision of the patients according to White classes, presence of family predisposition, and ‘good’ or ‘bad’ obstetrical history also failed to demonstrate any significant deviations. In 375 (diabetic) mother/child pairs the segregation of the ABO and Rhesus types in the children were in accordance with the expected values except for a few, probably random, deviations found in the children of Rhesus negative mothers. The present material of young diabetics did not support the assumption of any correlation between the ABO and Rhesus types and diabetes mellitus. There was no evidence of increased fetal wastage associated with these blood types.

Objective Physical activity reduces the risk of pregnancy-related complications. However, pregnant women often reduce their physical activity levels and do not follow the WHO’s physical activity recommendations during pregnancy. To support pregnant women in monitoring physical activity, the self-administered Pregnancy Physical Activity Questionnaire was developed in the US. We translated and cross-cultural adapted the questionnaire using the dual approach method. Meanwhile, and without knowing this, another Danish group simultaneously translated the questionnaire using the method described by Beaton et al. The aim is to present our data and discuss the unplanned purpose of comparing the results from using two different translation methods. Results We translated and cross-culturally adapted the Pregnancy Physical Activity Questionnaire to Danish with the following findings. Two additional items for cycling were included. Three items about spending time on a computer, reading, writing or talking on the phone were not feasible in terms of differentiating between them and these were merged into one item. The item ‘Taking care of an older adult’ was found to be irrelevant in a Danish setting and was removed. Adaptions were similar comparing the two methods. Consequently, using the dual-panel and the methods suggested by Beaton et al. yield similar results when translating and cultural adapting the PPAQ.

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