# Presentation: 510212

## Self- vs. Interviewer-administered Physical Activity Measures

- Leslie A. Pruitt, Ph.D.
- Center for Research in Disease Prevention
- Stanford University School of Medicine

## Presentation Outline

- 3.	Reliability, validity & detection of change

- Features of self- and interviewer- administered modes

- 4.	Which mode is best?

## Self-Administered Features

- Definition: 	“participant-driven” mode of collecting self-reported physical activity data

- Data may be collected by mail, on site, or internet

- Low cost (staff time)

- Must match respondents’ ages, educational levels

- Potential for use as part of behavior change intervention

**Notes:**
Participant-driven method of collecting self-reported physical activity data, without assistance
Low-cost in terms of required staff time and cost, which makes it a feasible mode to use for large population surveys
Must match respondents’ ages and educational levels; very dependent on a clear understanding by the participant, else may lead to incomplete data (missing or incomplete answers)

Potential for us as part of behavior change intervention – the process of completing such questionnaires or activity logs may serve to “educate” respondents as to what type of behavior is considered “physically active.”

## Interviewer-Administered Features

- Definition: “staff-driven” mode of collecting self-reported physical activity data

- Data may be collected by telephone or in person

- Moderate cost (staff time)

- Reduces risk of incomplete dataset

- May be combined with self-administered mode

**Notes:**
“Staff-driven” or staff supported mode of collecting self-reported physical activity data; interviewer, using prepared form or script, records answers to questions about activity

Moderate cost in terms of time necessary for interviewer training, establishment of inter-rater reliability, dealing with staff turnover, etc.

Reduces risk of incomplete dataset due to misunderstanding among respondents; allows for query/clarification with regard to intensity levels of activities; many subjects have difficulty in estimating activity intensity levels. Furthermore, there is evidence that strenuous activity is recalled more accurately than moderate activity (Taylor et al. Am J Epidemiol 120:818-824, 1984)

Combination approach:
Some questionnaires use both modes – respondent completes a questionnaire and, after studying the responses, the interviewer probes to either clarify or cross-check responses

## Interviewer-administered Questionnaires

| 
Questionnaire | Activity components | 
Population |
| --- | --- | --- |
| 7-Day Physical Activity Recall (PAR) | Leisure, work | 
Adult |
| YALE Physical Activity Survey | Household, exercise, recreational | Older adult |
| Minnesota Leisure-Time Physical Activity Questionnaire (MLTPA) | Leisure, household | Adult |
| National Health Interview Survey (NHIS) | Leisure, work | Adult |

**Notes:**
Explain format of next several slides; population refers to how it is being used in the BCC; PAR & YPAS are two most popular interviewer-administered questionnaires being used in BCC
7-d PAR
Time frame of recall: Past 7 days; Time to administer: 15-20 min
PAR is semi-structured interview that estimates an individual’s time spent in physical activity, strength, and flexibility exercises for the 7 days prior to the interview
The interviewer guides the participant through the recall process, day-by-day, to determine duration and intensity of activities
Outcome: kcal/wk or kcal/kg/wk
YPAS
Time frame: typical week in preceding month; Time to administer: about 20 min
36-item survey which calculates outcome: total activity time (hr/wk), EE index (kcal/wk), Activity dimension score (vigorous, sitting, standing, moving)
MLTPA Questionnaire
Time frame of recall: Past 12 months; Time to administer: 10-20 min
Consists of a list of 63 sports, recreational, yard, and household activities
Participant is instructed to report whether or not they performed the activity in the last 12 months; “yes” responses are followed up with additional probing from interviewer; Outcome: Total Activity Metabolic Index (AMI) per yr, week, day  (intensity)x (duration) x (frequency) x (number of mo/yr)
NHIS
Time frame of recall: Past 2 weeks; Time to administer: ?
Standardized form is used
Outcome: kcal/kg/wk which is used to categorize people into various activity patterns

## Self- or Interviewer-administered Questionnaires

| 
Questionnaire | Activity Components | 
Population |
| --- | --- | --- |
| CHAMPS Physical Activity Questionnaire | Household, exercise, recreational | Older adult |
| PASE (Physical Activity Scale for the Elderly) | Household, work, leisure | Older adult |
| Paffenbarger/
Harvard Alumni | Leisure | Adult |

**Notes:**
CHAMPS (4x) is most popular questionnaire for self- or interviewer-administered mode
CHAMPS
Time frame: 4 week; time to administer: 10-15 min
Outcome measure: frequency per week, caloric expenditure per week. For both frequency and caloric expenditure, 2 measures were derived based on: physical activities of > moderate intensity (MET > 3.0) and all specified physical activities which includes activities of light intensity in addition to activities of moderate or greater
PASE
Time frame: Past 7 days; time to administer: ?
10-item questionnaire; Outcome measure: unitless activity score (multiplying the amount of time spent in each activity (hr/wk) or participation (yes/no) in an activity by empirically derived item weights and summing over all activities; frequency and duration of household activities is not requested
Paffenbarger
Time frame: Past week or past year; time to administer: ?
Individual asked about walking, stair climbing and information on recreation and sports play; Outcome measure: kcal/week

## Self-administered Questionnaires

| 
Questionnaire | Activity Components | 
Population |
| --- | --- | --- |
| PDPAR (Previous Day Physical Activity Recall) | Work, leisure, transport | Youth |
| ACTIVITYGRAM | Lifestyle, recreational | Youth |
| KPAS (Kaiser Physical Activity Survey) | Household/care-giving, work, exercise | Adult women |
| Physical Activity Diary/Exercise Log | Exercise, recreational | Adult |

**Notes:**
No preferred self-administered questionnaire among BCC
PDPAR (jr high, high school)
Time frame: 1-day; time to administer: ?
Requires recall of previous day’s activities for after school hours and their relative intensities
Outcome measure: energy expenditure (kcal/kg)
ACTIVITYGRAM
Time frame: ?; Time to administer: ?
Computerized activity assessment
Conceptually similar to PDPAR; one difference is that the assessment accommodates in-school activity as well as activity done on weekends
Outcome measure: number of minutes of activity, tallies different types of activities reported (lifestyle, aerobic activity, aerobic sports, muscular activity, flexibility, rest)
KPAS
Time frame: past year; Time to administer: 20 min
75-item survey designed to obtain information about women’s physical activity habits
Outcome measure: Activity index from housework/caregiving, occupation, active living habits, sports/exercise items
PA Diary/Logs
Time frame: 24 h – 2 weeks; 7 days common; tedious
Individual logs one’s own activities periodically
Outcome measure: physical activity energy expenditure (METs, kcals)

## BCC Questionnaires by Population

- Youth

- PDPAR (self)

- ACTIVITYGRAM (self)

- Adult

- 7-Day PAR
- (interviewer)

- Older Adult

- YALE
- (interviewer)

- CHAMPS (either)

## Reliability & Mode of Administration

- Questionnaire (mode)		Re-test reliability

- PDPAR (S)				0.98 (same day)
- ACTIVITYGRAM (S)			?

- 7-Day PAR (I)			0.86 (same day)
- YALE	(I)				0.56 – 0.65 (2-wk)

- CHAMPS (E)			0.62 – 0.67 (6-mo)

## Validity & Mode of Administration

- Questionnaire (mode)	Validity (criterion)

- PDPAR (self)	0.77 (Caltrac)
- ACTIVITYGRAM (self)	0.58, 0.20 (BioTrainer)

- 7-Day PAR (interview)	0.49 (Caltrac)
- YALE (interview)	0.37 (Caltrac)

- CHAMPS (either)	Known-groups validity; health measures (0.17 – 0.30)

**Notes:**
Notes:
ACTIVITYGRAM: lower correlation on weekdays due to compressed range of activity scores
7-day PAR: Caltrac METs over 7 days (Montoye book)
YALE: correlation with “summary score” outcome measure of YPAS
CHAMPS: Questionnaire measures significantly discriminated across 3 groups known to vary in their physical activity levels based on prior, detailed assessment of their activity levels; Correlations between caloric expenditure measures and lower body functioning, 6- min walk, self-reported physical functioning and self-reported energy/fatigue are reported in the slide.

## Which Mode to Use?

- Low participant “cost”

- Low staff “cost”

- Data quality

- Ease of data collection

- Self	Interview

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## Summary

- Choice of self- vs interviewer-administered mode dependent upon:

- Population

- Resources

- Purpose

**Notes:**
Purpose: part of an intervention? What level of detail is required?
Population: literacy level, level of understanding of questionnaire
Resources: staff and money available