1 class 8 choosing measures to pretest, creating a questionnaire and questionnaire guide, methods...

1

Class 8

Choosing Measures to Pretest, Creating a Questionnaire and Questionnaire Guide, Methods for

Pretesting Measures

November 9, 2006

Anita L. Stewart Institute for Health & Aging

University of California, San Francisco

2

Basic Steps in Selecting Appropriate Measures

1. Specify context 2. Define concept for your study3. Identify and review potential measures for

a) conceptual and psychometric adequacyb) practicality and acceptabilityc) translation available if needed

4. Select best candidates5. Pretest selected measures in your target population6. Choose best ones based on pretest results OR7. Adapt if necessary to address problems

3

Overview of Class 8

Choosing measures for pretesting Creating a questionnaire and a guide to

measures in your questionnaire Methods for pretesting measures

4

4. Select Best Candidate Measures of Your Concept to Pretest

Select best measures for all concepts in your conceptual framework– Preferably at least 2 measures per concept

Pay special attention to priority concepts– Outcome measures or main independent

variables

5

Strategies for Selecting Best Measures

Select existing instrument in its entirety Select subscales of relevant domains from

existing instruments– only those that meet your needs

Supplement existing instrument with additional measures– core plus modules approach

6

What if no “Best” Measure?

For priority concepts with inadequate measure, could select optimal measure and adapt or modify

For priority concepts with no measure, may require development of new measure

7

Overview of Class 8

Choosing measures for pretesting Creating a questionnaire and a guide to

measures in your questionnaire Methods for pretesting measures

8

Process of Creating Questionnaire

A. Introduction

B. Statement of confidentiality

C. Length

D. Sections, section headings to break it up

E. Order of questions, measures

F. Formatting

G. Conclusion

9

Process A. Introduction

Inform respondent of purpose of overall study and of this questionnaire

Who is conducting the study Topics included Expected time to complete Assurance that participation is voluntary,

can skip any questions Specific instructions for completing

10

Process B. Statement of Confidentiality

Purpose: inform respondents of extent to which their answers are protected if there are risks to confidentiality, state them

Sample Statement: “All information that would permit identification of

individuals will be regarded as strictly confidential, will be used for purposes of evaluating the study, and will not be disclosed or released for any other purposes without prior consent, except as required by law.”

11

Statement of Confidentiality (cont.)

Note that this is a very high reading level Would need to simplify for lower SES

group

12

Process C. Length of Questionnaire

Acceptable length depends on: Commitment of respondents to topic area Health, free time of respondents

Short forms of most measures can help For those too ill or busy to complete long

survey Minimizes bias due to systematic nonresponse

of those more ill

13

Process D. Sections of Questionnaire

Break up with sections, grouped by topic (minimizes psychological burden)

Introduce new topics with– Phrases - “the next questions are about how

you’ve been feeling”

– Simple section headings, e.g.,

How You’ve Been Feeling

14

Process E. Question Order

Order can affect willingness to complete survey

Begin with general questions– Easy, non-threatening, interesting, related to

purpose of study Proceed with more specific questions,

more personal and sensitive questions Conclude with demographics (least

interesting, sensitive)

15

Process F. Formatting Self-Administered Questionnaires

Goal - make the tasks of reading questions, following instructions, and recording answers as easy as possible for respondents – Clear instructions for indicating their answer

– Easy to track separate questions

16

Principles of Formatting

Create a lot of space on page Use very light background for best contrast Number all questions Allow sufficient space for open-ended

questions– Lines far enough apart for large script

Special issues for older adults:– Larger font size (14)– Higher contrast (black on white)

17

Indicate How to Respond

Give specific instructions for answering questions, e.g.,– Circle all that apply

– Circle one number

– Put a check in the box that best represents howyou feel

If no instructions, subjects will have to figure out what to do and may not do it correctly

18

Types of Formats: Horizontal

How would you rate your health in general?

(circle one number)

1 Excellent 2 Good 3 Fair 4 Poor

(easy to get confused)

19

Types of Formats: Horizontal

How would you rate your health in general?

(check one box)

Excellent Good Fair Poor

(Still easy to get confused)

20

Types of Formats: Vertical

(circle one number)

No, not limited at all ........... 1

Yes, limited a little .......….. 2

Yes, limited a lot ...........…. 3

During the past 4 weeks, did your healthlimit you in walking one block..

21

Types of Formats: Matrix (circle one number)

How often during thepast 4 weeks did No, not Yes, Yes,your health limit limited limited limitedyou in ... at all a little a lot

Walking one block 1 2 3

Walking several blocks 1 2 3

Climbing 1 flight of stairs 1 2 3

22

Types of Formats: Matrix with Boxes

(Check one box on each row)How often during thepast 4 weeks did No, not Yes, Yes,your health limit limited limited limitedyou in ... at all a little a lot

Walking one block � � �Walking several blocks � � �Climbing 1 flight of stairs � � �

Easier to administer, but harder for data entry

23

Process G. Conclude Questionnaire

Add a brief thank you for completing the questionnaire (for their time and effort)

If questionnaire is to be mailed back, include instructions for mailing– Always include a pre-stamped, preaddressed

return envelope

24

Sample Questionnaires

See sample questionnaires– (sample formats)

25

Questionnaire Guide: Organization of Survey Content Identifies purpose of each measure in the

survey (questionnaire)– Describes source of data, time points– Describes the number of scales for each

measure Documents sources of measures and items

before you forget For modified measures, helps you know

exactly how you modified it

26

See Organization of Survey Content Handout Type of variable Concept Measure Data source Data points Number of items/survey question numbers Number of scores or scales for each measure References for measure sources

27

Overview of Class 8

Choosing measures for pretesting Creating a questionnaire and a guide to

measures in your questionnaire Methods for pretesting measures

28

Step 5: Pretest in Target Population Pretesting essential for measures being applied

to any new population group– Especially priority measures (e.g., outcomes)

Pretest is to identify:– problems with method of administration,

respondent burden, procedures– problems with questions or response choices

29

Types of Pretests

General debriefing pretest (N=10) In-depth cognitive interviewing

(N=5-10 each group) Large pretest (N=100)

– test measurement properties prior to major study

30

Types of Pretests

General debriefing pretest (N=10) In-depth cognitive interviewing

(N=5-10 each group) Large pretest (N=100)

– test measurement properties prior to major study

31

General Debriefing Pretest

Goal

– Identify problems with the procedures

– Estimate time needed to complete instrument

– Identify serious problems with items Procedures

– Subjects answer entire questionnaire

– At end, debrief

– Close to true task

32

Debriefing Questions After Administration of Survey..

Ask respondents: Were any questions confusing? Which words were hard to understand? Which questions were difficult to answer?

caused distress? Was questionnaire too long? Confusing instructions?

33

Patient Acceptance Scale

6-item scale about burden of a survey Negative affect burden

– Feeling embarrassed, upset, annoyed, uncomfortable

Questionnaire length Ease of answering questionnaire

Zimmerman M et al., Med Care, 1994;32:603-608

34

Example of General Pretest to Select Best Measure of Patient Satisfaction

Compared 4 questionnaires on– Response rates, missing data, completion time,

patient ratings of the questionnaire 10 evaluation items at end of questionnaire

– Clarity of questions, ease of finding an answer, questions about unimportant issues, ease of completion, too long, layout confusing, lacked important questions

Perneger TV et al., A randomized trial of four patient satisfactionquestionnaires Med Care, 2003;41(12):1343-1352

35

Example of General Pretest to Select Best Measure of Patient Satisfaction

Compared 4 questionnaires on– Response rates, missing data, completion time,

patient ratings of the questionnaire 10 evaluation items at end of questionnaire

– Clarity of questions, ease of finding an answer, questions about unimportant issues, ease of completion, too long, layout confusing, lacked important questions

Perneger TV et al., A randomized trial of four patient satisfactionquestionnaires Med Care, 2003;41(12):1343-1352

36

Problems with General Pretests

Respondents… often don’t understand the task. don’t want to appear as if they didn’t

understand have a hard time telling you anything was

wrong easier to say everything was fine

37

Types of Pretests

General debriefing pretest (N=10) In-depth cognitive interviewing

(N=5-10 each group) Large pretest (N=100)

– test measurement properties prior to major study

38

In-Depth Cognitive Interviews

Derived from social and cognitive psychology to explore processes respondents use to answer survey questions

39

Cognitive Interviews Examine 4 Steps in Answering Questions

Comprehend the question (as intended) Retrieve the information

– various strategies used to access memory Judgment formation - formulate an answer

– calculate or judge the correct information Edit response - decide what to report

– is answer embarrassing, socially undesirable?

Sudman S et al., Thinking About Answers, Jossey-Bass, San Francisco, 1996

40

Purpose of Cognitive Interviews

To learn .. .. if respondents understand words and phrases

as intended (meaning) .. about the process of answering the questions .. whether items are unacceptable .. about the usefulness of response choices

– whether response choices are adequate

– how they use the response choices

41

Two Types of Cognitive Interviews

Think aloud interviews– Respondent asked to think aloud as they

answer question Probe interviews

– Interviewer asks specific questions to elicit how respondent answered question

– Scripted and spontaneous probing

42

Think Aloud Interviews

Thorough examination of the entire thought process of creating answers

Require that respondents verbalize their thought processes as they are answering items– Hard task for most people

Mostly done at “cognitive interviewing” labs, e.g., at National Institutes of Health

43

Steps in Cognitive Interview Pretesting

Identify most problematic items and develop scripted “probes”

Decide on order of administration– Probes after each question or at the end

Recruit sample for cognitive interviews Administer entire questionnaire

– Administer probe questions Summarize results

44

Probe Questions to Explore Meaning

What does the word _______ mean to you?

What does the phrase ________ mean to you?

45

Example:Probing the Meaning of a Phrase

I asked you about how the office staff treated you personally ….

What does the phrase “office staff” mean to you?

46

Example:Probing the Meaning of a Phrase

What does the phrase “office staff” mean to you?

“the receptionist and the nurses”

“nurses and appointment people”

“the person who takes your blood pressure and the clerk in the front office”

47

Example:Probing the Meaning of a Phrase

What does the phrase “office staff” mean to you?

“the receptionist and the nurses”

“nurses and appointment people”

“the person who takes your blood pressure and the clerk in the front office”

We changed the question to receptionist and appointment staff

48

Types of Probes (cont.)

Retrieval– How did you remember that?

Judgment– Why did you pick that number for your answer?

Response– Do you think that most people answer this

question honestly?Collins D. Quality of Life Research 2003. 12:229-38.

49

Types of Probes (cont.) Redundancy

– How is the phrase “give you advice about your diet and exercise” different from the phrase “talk to you about your diet and exercise”?

50

Types of Cognitive Probes (cont.)

Cultural appropriateness and meaning:– I asked you how often doctors asked you about

your health beliefs? What does the term ‘health beliefs’ mean to you?

“.. I don’t want medicine” “.. How I feel, if I was exercising…” “.. Like religion? --not believing in

going to doctors?”

51

Types of Cognitive Probes (cont.)

Cultural appropriateness and meaning:– I asked you how often doctors asked you about

your health beliefs? What does the term ‘health beliefs’ mean to you?

“.. I don’t want medicine” “.. How I feel, if I was exercising…” “.. Like religion? --not believing in

going to doctors?” We changed the question to “personal beliefs

about your health”

52

Overcoming “Social Desirability” in Cognitive Interviews

Ask respondents whether they think others…– would have difficulty answering a question

– would answer the question honestly

53

Example of Probe on Difficulty: CES-D Item

“During the past week, how often have you felt that you could not shake off the blues, even with help from family and friends”

Probe: Do you feel this is a question that people would or would not have difficulty understanding?– Latinos more likely than other groups to report

people would have difficulty

TP Johnson, Health Survey Research Methods, 1996

54

Example:Probing the Process of Answering

I asked you _____ and you answered____. – Why did you pick this answer?– What were you thinking of when you picked this

answer? – Can you tell me what you were thinking when

you answered this way?»Can you give me some examples?

What came to mind when I asked you _____?

55

Example: Use of Response Scale

Do diverse groups use the response scale in similar ways?

Re questions about cultural competence of providers– Interviewers reported that Asian respondents

who were completely satisfied did not like to use the highest score on the rating scale

CPEHN Report, 2001

56

Sample Result: Use of Response Scale

In an exercise class of Samoans, instructor asked them to rate the difficulty of the exercise he just did on a 1-10 scale

They did not understand what he meant by a 1-10 scale – “Western” metric?

57

Cognitive Interviewing:Example of Probing Questions

Acceptability of Questions I asked you _____.

– Did you find this question offensive?

– Was it distressing to answer this question?

58

Example of Probe for Acceptability

When I asked you how often you felt discriminated against by doctors because of your race or ethnicity, you answered (read answer given).– Were you offended by this question?

59

Steps in Cognitive Interview Pretesting

Identify most problematic items and develop scripted “probes”

Decide on order of administration– Probes after each question or at the end

Recruit sample for cognitive interviews Administer entire questionnaire

– Administer probe questions Summarize results

60

Handouts: Examples of Probe Questions

Sample Cognitive Interview Protocol– Ron Hays and Leo Morales

Selected probes from Interpersonal Processes of Care study

Summary of NCHS working paper series on cognitive methods (website)

61

Homework for Week 9

Create a short “questionnaire” of the measure, including instructions

Identify 4-5 questions in the measure you selected that might be a problem for your target population

– Phrases, length, response choices Write a “probe” question for each problem

– Include some on the meaning of a word or phrase and some on the adequacy of the response choices.

62

Vogt et al.

Role of focus groups in adapting measures for diverse populations

How focus groups led to expansion and addition of constructs, confirmation of existing items, and identification of relevant quotes that could be used for new items

Appendices provide examples of construct definitions and a focus group guide

63

Harris-Kojetin Reading

Example of Measure Undergoing Cognitive Testing – Consumer Assessment of Health Plans Study

(CAHPSTM) Describes extensive pretesting in

developing and refining the CAHPSTM

Provides example of good pretesting

64

Pasick et al. reading

Provides examples of what can be learned through various types of pretests

Methods included– interviewing investigators and interviewers– focus groups– cognitive interview testing

Suggests that for important measures, multiple approaches to pretesting are useful

65

Switzer et al. reading

From class 3 section of class binder p 405-406 – modifying measures