Measuring Physical Activity for Research

 1.     Findthree peer-reviewed studies that haveinvestigated the validity of measuringphysical activity with one of the assessment types used in this project (eitherthe app/device you used, BPAL, APAR, MAQ, SBAS, or BRFSS). Every study musthave used the same assessment type/instrument. Acceptable measures of PAinclude METmin, minutes of light/moderate/vigorous PA, steps per day (or otherspecified amount of time), heart rate, estimated oxygen uptake (i.e., VO2),energy expenditure (i.e., kcal), etc. Summarize the following for each study:

a.     The purpose of the study. Summarize thepurpose of the study in your own words.

b.     The sample characteristics. At minimum,provide averages, medians, ranges, standard deviations, or percentages, asappropriate, regarding age, sex, and race of the sample. Statistics regardingBMI, socioeconomic status, educational attainment, etc. may also be providedbut are not mandatory.

c.     Physical activity data collection with theinstrument you chose. Describe in detail how the instrument was used tocollect physical activity data. E.g., How often was data collected? When wasdata collected (at what point during the study, what days of the week, what timeof day)? Were the participants given detailed instructions? Was an abbreviatedversion of the instrument used or the full version?

d.     Criterion measure of physical activity.How was the validity of the chosen instrument determined? In other words, whatother way of measuring physical activity levels was the instrument compared to(i.e., what was used as the criterion measure)? Describe this instrument. Whenwas the data with this other instrument collected? Was data collected with bothinstruments at the same time or at different times (hint: The data should becollected at the same time)?

e.     Validity of the instrument. How validwas the physical activity measuring instrument when compared to the criterionmeasure? Report at least one statistic (e.g., correlation coefficient (r),coefficient of variation (R²), intraclass correlation coefficient(ICC), mean absolute percent error [MAPE], etc.)

Summarize the overall validity of theinstrument based on the 3 studies. Answer these questions:

1)    Whatis the instrument supposed to measure and do you think it does measure thiswith acceptable validity/accuracy?

2)    Whatare the strengths of the instrument? Is there any characteristic that makes itparticularly useful or practical?

3)    Whatare the weaknesses of the instrument?