The Effect of Question Order on Reporting Physical Activity and Walking Behavior

Transcription

1 Uiversity of South Carolia Scholar Commos Faculty Publicatios Physical Activity ad Public Health The Effect of Questio Order o Reportig Physical Activity ad Walkig Behavior Bret E. Hutto Patricia A. Sharpe Uiversity of South Carolia - Columbia, SHARPEP@mailbox.sc.edu Michelle L. Graer Cheryl L. Addy Uiversity of South Carolia - Columbia, caddy@sc.edu Steve P. Hooker Uiversity of South Carolia - Columbia Follow this ad additioal works at: sph_physical_activity_public_health_facpub Part of the Public Health Commos Publicatio Ifo Published i Joural of Physical Activity ad Health, Volume 5, Issue Supplemet 1, 2008, pages S16-S29. Hutto, B., Sharpe, P. A., Graer, M. L., Addy, C. L., & Hooker, S. (2008). The effect of questio order o reportig physical activity ad walkig behavior. Joural of Physical Activity ad Health, 5(Supplemet 1), S16-S29. Joural of Physical Activity ad Health, 2008, Huma Kietics This Article is brought to you for free ad ope access by the Physical Activity ad Public Health at Scholar Commos. It has bee accepted for iclusio i Faculty Publicatios by a authorized admiistrator of Scholar Commos. For more iformatio, please cotact SCHOLARC@mailbox.sc.edu.

2 Joural of Physical Activity & Health, 2008, 5, Supp 1, S16-S Huma Kietics, Ic. The Effect of Questio Order o Reportig Physical Activity ad Walkig Behavior Bret Hutto, Patricia A. Sharpe, Michelle L. Graer, Cheryl L. Addy, ad Steve Hooker Backgroud: Questio order might affect self-reported regular physical activity (PA) measured with items from the Behavioral Risk Factor Surveillace System (BRFSS) PA module. Methods: A telephoe survey was coducted usig 2 forms (N = 1004, N = 212) with varyig PA questio order. The stadard form preseted moderate- PA, vigorous-pa, ad walkig questios, i that order, whereas the alterate form preseted walkig questios, followed by moderate-pa, ad the vigorous-pa questios. Weighted, adjusted rates of vigorous PA, walkig, meetig the Ceters for Disease Cotrol ad Prevetio (CDC) recommedatio for moderate or vigorous PA, ad moderate PA from each form were compared. Results: Vigorous PA ad walkig were similar regardless of questio order. Meetig the CDC recommedatio for moderate or vigorous PA was reported less ofte with the alterate form amog 18- to 34-year-olds. Less moderate PA was reported with the alterate form overall ad amog 18- to 34-year-olds, wome, whites, ad those with a high school educatio or less. Coclusio: Estimatig PA ad walkig across sociodemographic strata with differig patters of PA requires askig moderate-pa ad vigorous-pa questios before walkig questios. Askig walkig questios first might lead to bias, especially for moderate PA. Walkig, added to a survey with BRFSS moderate ad vigorous PA items, should be placed after moderate ad vigorous PA. Walkig questios first may cause bias, especially for moderate PA. Keywords: survey, BRFSS, moderate physical activity, vigorous physical activity Measuremet of physical activity (PA) i populatio surveys is complicated by varyig defiitios of PA ad by questioaire-desig issues. The Ceters for Disease Cotrol ad Prevetio s (CDC) Behavioral Risk Factor Surveillace System (BRFSS) is a importat large-scale survey used for settig atioal health priorities ad moitorig progress toward the Healthy People 2010 objectives at the state ad atioal levels. Use of items from the BRFSS PA module might appeal to researchers ad practitioers iterested i assessig whether study populatios meet atioal PA recommedatios for moderate or vigorous PA. For use i large samples, the curret BRFSS PA module 1 elicits frequecy ad duratio of PA Hutto, Sharpe, ad Hooker are with the Prevetio Research Ceter, ad Addy the Dept of Epidemiology ad Biostatistics, Arold School of Public Health, Uiversity of South Carolia, Columbia, SC Graer is with the School of Public Health, Uiversity of Nevada, Reo, NV S16

3 Effect of Questio Order S17 with 3 questios about moderate-itesity activity followed by 3 questios about vigorous-itesity activity. Details of the developmet ad validatio of the curret BRFSS PA items have bee published by Aisworth et al 2 ad Macera et al. 3 To measure walkig as a specific behavior, a set of 3 walkig questios aalogous to the 6 BRFSS questios about moderate ad vigorous PA were added to the survey. Addig questios to a existig istrumet could affect resposes to the origial PA questios, yieldig rates of PA that are ot comparable to studies usig oly the origial 6 items. Ham ad colleagues 4 recetly examied the effect of questio order o rates of PA as estimated i 3 surveys usig BRFSS ad other questios, fidig evidece of a form effect, although these results might have bee cofouded with other differeces i the wordig of the items. The curret study was desiged to isolate potetial effects of questio order o self-reported PA behavior whe such walkig questios are used. Two forms of a telephoe survey istrumet were admiistered to radomly draw samples from a sigle populatio. The oly differece betwee the survey forms was whether the walkig questios were asked immediately before or immediately after the BRFSS moderate- ad vigorous-pa items. This article presets the relatioship betwee questio order ad rates of moderate ad vigorous PA ad walkig, overall ad i certai sociodemographic categories. The Survey Methods A list-assisted, radom-digit-dialed telephoe survey was coducted with 1216 oistitutioalized adults 18 years ad older i a cetral South Carolia couty by ORC Macro of Burligto, VT. Iterviews averagig 18.6 miutes were completed betwee May 15 ad Jue 23, The respose rate was 32.9% usig the Coucil of America Survey Research Orgaizatios s respose-rate formula. 5 The survey s weights were based o 3 compoets: differetial probabilities of selectio; a poststratificatio factor adjustig weighted totals to 2000 cesus populatio figures by age, race/ethicity, ad geder; ad a factor combiig the stadard ad alterate survey forms. The survey was coducted as part of a ogoig PA study that was reviewed ad approved as compliat with the istitutio s huma-subjects requiremets. The questioaire icluded either a stadard form or a alterate versio i which the walkig questios were asked first so as to study the effect of questio order o aswers to the walkig, moderate-pa, ad vigorous-pa questios. This was the sole differece betwee the 2 versios. See Appedix 1 for the stadard versio of the questios (BRFSS items followed by walkig questios) ad Appedix 2 for the alterate form (walkig questios followed by BRFSS items). This aalysis used 1004 respodets who received the stadard versio of the survey with the BRFSS PA questios asked first ad 212 respodets who received the alterate versio with walkig questios asked first. Of these 1216 respodets, 120 had icomplete, out-of-rage, or missig resposes for PA or demographic covariates (96 stadard-form questioaire respodets ad 24 alterate-form questioaire respodets); the aalysis data set, therefore, icluded 908 stadard-form ad 188 alterate-form questioaire respodets, for a total of 1096 respodets. The 120 respodets with missig data did ot differ sigificatly from the complete cases o sociodemographic characteristics, walkig, moderate PA, or vigorous

4 S18 Hutto et al PA. All respodets met age ( 18 years) ad residece criteria (residet 4 d/wk, 6 mo/y), ad all were physically able to leave the house for a walk without assistace ad either completely or partially physically able to egage i a sample list of moderate activities (eg, housework, exercise, gardeig). Thus, oly adult residets who were able to walk were icluded i the sample. Aalysis A cesus-weightig variable, based o couty-level estimates from the US Cesus Bureau, was used to weight the data by age, race, ad geder. The MULTILOG procedure i SUDAAN was used to compute weighted proportios i each walkig or PA category, adjusted for sociodemographic factors, usig logistic regressio. These adjusted weighted proportios are aalogous to adjusted group meas i liear models 6 ad are available usig the PREDMARG statemet i SUDAAN. Dichotomous outcome variables correspodig to PA ad walkig behaviors were regressed o a dichotomous stadard/alterate-form variable alog with age, sex, race, educatio, employmet status, ad 2-way iteractios betwee form ad each sociodemographic factor. The survey script istructed respodets to cosider total daily accumulatio of activity takig place i cotiuous itervals of 10 miutes or more. Adjusted proportios of the populatio reportig the followig 4 behaviors were computed for the 2 differet questio orders: Egagig i 20 or more miutes per day of accumulated vigorous PA o 3 or more days per week Egagig i 30 or more miutes per day of accumulated moderate PA o 5 or more days per week Meetig the CDC/America College of Sports Medicie (ACSM) recommedatio for accumulated moderate or vigorous PA, defied herei as either 30 or more miutes per day of moderate PA o 5 or more days per week or 20 or more miutes per day of vigorous PA o 3 or more days per week Walkig for 30 or more accumulated miutes per day o 5 or more days per week These adjusted proportios were also estimated separately withi 2 or 3 strata each of age, sex, race, educatio, ad employmet alog with a Wald test of statistical sigificace for the questio-order effect i each stratum. Results There were o statistically sigificat differeces at the α =.05 level betwee the sociodemographic characteristics of the stadard- ad alterate-form subsamples. Sociodemographic characteristics of the respodets that were admiistered each survey form are preseted i Table 1 (weighted proportios i each category). Vigorous PA Regular vigorous PA (3 or more days, 20 miutes or more) differed oly 2.3% by questio order i the overall sample, with the slightly higher-reported rate beig

5 Effect of Questio Order S19 Table 1 Demographic Characteristics of the Sample a Stadard form (BRFSS questios first) Alterate form (walkig questios first) Age, mea (SD) 41.5 (15.9) 43.7 (16.1) Sex female 51.3% 55.5% male 48.7% 44.5% Race b white 55.9% 57.0% other 44.1% 43.0% Educatio high school graduate or less 40.1% 39.4% some college 33.4% 36.9% college graduate 26.5% 23.7% Employmet employed 65.0% 63.0% ot employed 35.0% 37.0% Abbreviatios: BRFSS, Behavioral Risk Factor Surveillace System. a Weighted proportios. b Overall race proportios were 56.1% white, 38.7% Africa America, ad 5.2% other. with the alterate form, i which walkig questios were asked first. As preseted i Table 2, i specific sociodemographic categories, differeces by questio order were small i magitude, ragig from 1.8% to 7.2%. These differeces are withi the rage of radom variatio expected give the small alterate-form sample size of 188 respodets. Noe of the stratum-specific differeces were statistically sigificat. Moderate PA Table 3 presets the results from a similar aalysis of regular moderate PA (5 or more days, 30 miutes or more). I cotrast to results for vigorous PA, the overall reported moderate-pa proportios differeces by questio order were larger ad statistically sigificat, with the proportio of respodets reportig regular moderate PA beig 9.8% lower whe respodets were asked walkig questios first tha whe respodets received the stadard questio order. The differece amog the 18- to 34-year-old subgroup was largest, with 17.7% more reportig regular moderate PA amog those receivig the stadard order (PA questios before walkig questios). Other large differeces were observed for wome (11.8%), whites (13.4%), ad those with a high school educatio or less (16.6%). All of these differeces were i the same directio as the overall results, ad all were statistically sigificat. Askig walkig questios first was associated with a smaller proportio of persos who report meetig the moderate-pa recommedatio (5 or more days, 30 miutes or more).

6 S20 Hutto et al Table 2 Effect of Questio Order o Regular Vigorous PA a by Sociodemographic Category Demographic Stadard form (BRFSS questios first) Adjusted % regular vigorous PA (SE) Alterate form (walkig questios first) Adjusted % regular vigorous PA (SE) Questioorder effect, P value Overall (1.6) (3.7).57 Age (y) (3.5) (6.8) (2.5) (5.9) (2.8) (6.4).33 Sex female (2.0) (4.6).79 male (2.6) (5.9).59 Race b white (2.1) (4.6).25 other (2.5) (6.0).74 Educatio HS graduate or less (2.5) (5.7).74 some college (2.9) (6.2).72 college graduate (3.3) (7.8).78 Employmet ot employed (3.1) (6.3).49 employed (2.1) (4.6).24 Abbreviatios: BRFSS, Behavioral Risk Factor Surveillace System; PA, physical activity; HS, high school. a Regular vigorous PA is defied as 20 miutes or more o 3 or more days per week. b Overall race proportios were 56.1% white, 38.7% Africa America, ad 5.2% other. Meetig the CDC Recommedatio for Moderate or Vigorous PA Table 4 shows the effects of questio order o meetig the CDC/ACSM PA recommedatio i age, sex, race, educatio, ad employmet subgroups. Askig the walkig questios first was associated with a very slight decrease (2.2%) i the proportio of respodets reportig regular moderate or vigorous PA. The sociodemographic stratum for which this differece was largest was the yougest age group, 18 to 34 years old, amog whom the questio order is associated with a differece of 13.7% (P =.05), with the higher rates of reported PA amog those receivig the questios i stadard order (PA questios before walkig questios). This stratum-specific differece was borderlie statistically sigificat.

7 Effect of Questio Order S21 Table 3 Effect of Questio Order o Regular Moderate PA a by Sociodemographic Category Demographic Stadard form (BRFSS questios first) Adjusted % regular moderate PA (SE) Alterate form (walkig questios first) Adjusted % regular moderate PA (SE) Questioorder effect, P value Overall (1.7) (3.6).02 Age (y) (3.6) (6.0) (2.7) (6.0) (2.8) (5.8).02 Sex female (2.2) (4.4).03 male (2.6) (5.8).27 Race b white (2.2) (4.7).02 other (2.5) (5.4).42 Educatio HS graduate or less (2.6) (5.2).02 some college (3.0) (6.2).57 college graduate (3.3) (7.7).31 Employmet ot employed (3.1) (6.1).16 employed (2.1) (4.5).06 Abbreviatios: BRFSS, Behavioral Risk Factor Surveillace System; PA, physical activity; HS, high school. a Regular moderate PA is defied as 30 miutes or more o 5 or more days per week. b Overall race proportios were 56.1% white, 38.7% Africa America, ad 5.2% other. Walkig There was little overall differece by questio order i reported regular walkig behavior, detailed i Table 5. The proportio (SE) reportig regular walkig (5 or more days, 30 miutes or more) was 3.3% smaller for the stadard form tha for the alterate form. For idividual sociodemographic strata, the differeces by questio order geerally raged from 0.5% to 9.6%. However, i the middle of the 3 educatio categories (Some College), the proportio reportig regular walkig was 13.3% greater for the alterate form tha for the stadard form (P =.05). Noe of the other stratum-specific differeces were statistically sigificat.

8 S22 Hutto et al Table 4 Effect of Questio Order o Meetig the CDC PA Recommedatio a by Sociodemographic Category Demographic Stadard form (BRFSS questios first) Adjusted % (SE) meetig CDC PA recommedatio Alterate form (walkig questios first) Adjusted % (SE) meetig CDC PA recommedatio Questioorder effect, P value Overall (1.7) (3.8).60 Age (y) (4.0) (7.3) (2.7) (5.9) (2.7) (6.5).05 Sex female (2.2) (4.8).34 male (2.7) (5.9).84 Race b white (2.2) (4.8).17 other (2.7) (6.0).49 Educatio HS graduate (2.7) (6.2).25 or less some college (3.0) (6.0).88 college (3.3) (7.8).79 graduate Employmet ot employed (3.1) (6.5).55 employed (2.2) (4.7).84 Abbreviatios: CDC, Ceters for Disease Cotrol ad Prevetio; BRFSS, Behavioral Risk Factor Surveillace System; PA, physical activity; HS, high school. a The recommeded level of PA is either moderate activity for 30 miutes or more o 5 or more days per week or vigorous activity for 20 miutes or more o 3 or more days per week. b Overall race proportios were 56.1% white, 38.7% Africa America, ad 5.2% other. Discussio Choosig stadard survey items is ot sufficiet to esure that the resposes will be comparable to other surveys usig those questios. The cotext i which the items are preseted also matters, ad the results of this study suggest that PA rates derived from a survey ca be affected by variatios i the order of moderate PA, vigorous PA, ad walkig questios. Although the differece by questio order observed i the proportio meetig the CDC/ACSM recommedatio was miimal i this case, eve a small questio-order effect is troublig if such surveys are used for surveillace of populatio PA. For istace, other sources of systematic bias i PA reportig, such as seasoal effects, could be compouded by the effect of questio order. Actual chages i PA from year to year documeted through cross-sectioal surveys are at best very small i magitude o a whole-populatio

9 Effect of Questio Order S23 Table 5 Effect of Questio Order o Regular Walkig a by Sociodemographic Category Demographic Stadard form (BRFSS questios first) Adjusted % regular walkig (SE) Alterate form (walkig questios first) Adjusted % regular walkig (SE) Questioorder effect, P value Overall (1.7) (3.7).47 Age (y) (3.9) (7.0) (2.6) (5.7) (2.6) (6.5).42 Sex female (2.1) (4.6).37 male (2.6) (5.8).75 Race b white (2.2) (4.6).74 other (2.6) (5.8).12 Educatio HS graduate or less (2.6) (5.6).39 some college (2.9) (6.1).05 college graduate (3.2) (7.6).79 Employmet ot employed (2.7) (5.8).49 employed (2.2) (4.7).59 Abbreviatios: BRFSS, Behavioral Risk Factor Surveillace System; HS, high school. a Regular walkig is defied as 30 miutes or more o 5 or more days per week. b Overall race proportios were 56.1% white, 38.7% Africa America, ad 5.2% other. basis. Eve small measuremet biases might be eough to obscure a true chage. For moderate PA, the differeces i the measured proportio meetig the recommedatio with the walkig questios before ad after the BRFSS items were sufficietly large (11.8% to 17.7% depedig o sociodemographic stratum) to be a cause for cocer over the validity of studies usig this istrumet. I fact, the overall ad several of the stratum-specific differeces were statistically sigificat eve i this small alterate-form sample. Ham et al 4 compared the BRFSS with the Natioal Physical Activity Survey (NPAS) ad foud differeces i reported moderate ad vigorous PA betwee the 2 surveys, which differed primarily i questio order. Compared with the NPAS, which asked about moderate PA before vigorous PA, they foud lower reported rates of moderate PA with the versio of BRFSS i use at the time, i which questios about vigorous PA preceded those about moderate PA. The authors discussed the possibility that items perceived as repetitive might be edorsed less frequetly. Aother potetial issue arises whe combiig items about a specific moderate-itesity PA behavior such as walkig ad geeral moderate-pa questios. There might be overlap i the

10 S24 Hutto et al mid of the respodet betwee the costructs of walkig ad moderate PA. With walkig questios asked first, all or some respodets might attempt to report frequecy ad duratio of moderate PA i a way that does ot cout walkig as moderate PA. The curret study also foud differetial effects of questio order across sociodemographic categories. Eve whe ot comparig multiple surveys, the presece of walkig questios before the stadard BRFSS PA items could lead to icorrect ifereces cocerig differeces amog age, race, or geder groups. For istace, take i isolatio, the alterate-form data from this study would be iterpreted as showig a lower proportio of regular moderate ad vigorous PA amog 18- to 34-year-olds tha amog 35- to 54-year-olds (see Table 4). Coversely, the stadard form with the BRFSS PA items at the very begiig of the module (before the walkig items) shows that more 18- to 34-year-olds meet the PA recommedatio tha do 35- to 54- year-olds, which is the usual patter expected i populatio surveys. A possible factor cotributig to differetial questio-order effects could be variatio i the prevalece of specific moderate- ad vigorous-pa behaviors i each sociodemographic group. If, for istace, respodets were cofused as to whether walkig couts as moderate PA, the the magitude of the effect i ay stratum would deped o the proportio of moderate PA made up of walkig for members of that stratum. These results idicate that questio order matters whe icorporatig the BRFSS PA module i surveys, specifically that items cocerig moderate ad vigorous PA should be the first oes preseted to the respodet. Items about walkig yielded similar overall proportios whe used before or after moderatead vigorous-pa items (the large differece specific to the Some College stratum might have bee a chace occurrece because of the small size of that subgroup), whereas moderate-pa prevalece differed substatially depedig o whether moderate-pa items were asked before or after questios about walkig. This is a idicatio that if walkig questios are to be used, placig them after the stadard BRFSS moderate- ad vigorous-pa questios is preferred. Otherwise, the resultig estimates might ot be comparable i all sociodemographic subpopulatios with the rates measured by atioal surveillace surveys. Although this study was sufficiet for its iteded purpose of examiig overall populatio prevalece estimates for a possible effect of questio order, the sample size was too limited to draw defiite coclusios cocerig differetial effects across subpopulatios (ie, youger adults or the less educated). A future study that admiisters stadard ad alterate forms of the istrumet each to a large sample of 1000 or more respodets would have sufficiet statistical power to allow judgmet as to whether a apparet differece of 10% or more i strata-specific rates of selfreported PA is simply caused by chace or represets reproducible ad potetially problematic measuremet issues i the use of these survey questios. Aother very useful feature for a future study would be the admiistratio of a istrumet desiged to estimate eergy-expediture uits, such as metabolic equivalet miutes per day. Additioal qualitative testig, such as cogitive iterviewig, could address the possibility of costruct overlap i members of certai subpopulatios. Ackowledgmets This work was supported i part by Cooperative Agreemet umbers U48/CCU ad 1-U48-DP ad grat umber R06/CCR from the Ceters for Disease Cotrol ad Prevetio to the Uiversity of South Carolia Prevetio Research Ceter.

11 Effect of Questio Order S25 The cotets of this article are solely the resposibility of the authors ad do ot ecessarily represet the official views of the CDC. The authors appreciate the assistace of the Sumter Couty Active Lifestyles Coalitio i coductig this research. Refereces Behavioral risk factor surveillace system questioaire. Ceters for Disease Cotrol ad Prevetio Web site brfss.pdf. 2. Aisworth BE, Bassett DR Jr, Strath SJ, et al. Compariso of three methods for measurig the time spet i physical activity. Med Sci Sports Exerc. 2000;32(suppl 9): S457-S Macera CA, Joes CA, Yore MM, et al. Prevalece of physical activity, icludig lifestyle activities amog adults Uited States, Morb Mortal Wkly Rep. 2003;52: Ham SA, Macera CA, Joes DA, Aisworth BE, Turczy, KM. Cosideratios for physical activity research: variatios o a theme. J Phys Act Health. 2004;1: The America Associatio of Public Opiio Research. Stadard Defiitios: Fial Dispositios of Case Codes ad Outcome Rates for Surveys. 3rd ed. Leua, KS: The America Associatio for Public Opiio Research; Kor EL, Graubard BI. Aalysis of Health Statistics. New York, NY: Joh Wiley & Sos; Appedix 1 BRFSS Physical Activity (Stadard Form) For the ext questios, we are iterested i two types of physical activity: vigorous ad moderate. Vigorous activities cause large icreases i breathig or heart rate, ad moderate activities cause small icreases i breathig or heart rate. Now, thikig about the moderate activities you do whe you are ot workig at a paid job: NOTE: EMPHASIZE MODERATE 1. I a usual week, do you do moderate physical activities for at least 10 miutes at a time, such as brisk walkig, bicyclig, vacuumig, gardeig, or aythig else that causes small icreases i breathig or heart rate? 1 Yes 2 No {SKIP TO Q4} 7777 Do t kow/not sure {SKIP TO Q4} 9999 Refused {SKIP TO Q4} 2. O how may days per week do you usually do moderate physical activities for at least 10 miutes at a time? days

12 S26 Hutto et al 9999 Refused {GO TO Q4} 3. O days whe you do moderate activities for at least 10 miutes at a time, how much total time do you sped doig these activities? Hours Ad miutes Refused Now, thikig about the vigorous activities you do whe you are ot workig at a paid job: NOTE: EMPHASIZE VIGOROUS 4. I a usual week, do you do vigorous activities for at least 10 miutes at a time, such as ruig, aerobics, heavy yard work, or aythig else that causes large icreases i breathig or heart rate? 1 Yes 2 No {GO TO Q7} 7777 Do t kow/not sure {GO TO Q7} 9999 Refused {GO TO Q7} 5. O how may days per week do you do these vigorous activities for at least 10 miutes at a time? days 9999 Refused {GO TO Q7} 6. O days whe you do vigorous activities for at least 10 miutes at a time, how much total time do you sped doig these activities? Hours Ad miutes 9999 Refused

13 Effect of Questio Order S27 The ext 3 questios ask you about your walkig behavior SPECIFICALLY. 7. I a usual week, do you walk for at least 10 miutes at a time for recreatio, exercise, to get to ad from places, while at work, or for ay other reaso? 1 Yes 2 No {Skip to Q10} 7777 Do t kow/not sure {Skip to Q10} 9999 Refused {Skip to Q10} 8. How may days per week do you walk for at least 10 miutes at a time? days per week 9999 Refused {GO TO Q10} 9. O days whe you walk for at least 10 miutes at a time, how much total time per day do you sped walkig? Hours Ad miutes 9999 Refused Appedix 2 BRFSS Physical Activity (Alterate Form) The ext 3 questios ask you about your walkig behavior SPECIFICALLY. 1. I a usual week, do you walk for at least 10 miutes at a time for recreatio, exercise, to get to ad from places, while at work, or for ay other reaso? 1 Yes 2 No {Skip to Q10} 7777 Do t kow/not sure {Skip to Q10} 9999 Refused {Skip to Q10}

14 S28 Hutto et al 2. How may days per week do you walk for at least 10 miutes at a time? days per week 9999 Refused {GO TO Q10} 3. O days whe you walk for at least 10 miutes at a time, how much total time per day do you sped walkig? Hours Ad miutes 9999 Refused For the ext questios, we are iterested i two types of physical activity: vigorous ad moderate. Vigorous activities cause large icreases i breathig or heart rate, ad moderate activities cause small icreases i breathig or heart rate. Now, thikig about the moderate activities you do whe you are ot workig at a paid job: NOTE: EMPHASIZE MODERATE 4. I a usual week, do you do moderate physical activities for at least 10 miutes at a time, such as brisk walkig, bicyclig, vacuumig, gardeig, or aythig else that causes small icreases i breathig or heart rate? 1 Yes 2 No {SKIP TO Q4} 7777 Do t kow/not sure {SKIP TO Q4} 9999 Refused {SKIP TO Q4} 5. O how may days per week do you usually do moderate physical activities for at least 10 miutes at a time? days 9999 Refused {GO TO Q4}

15 Effect of Questio Order S29 6. O days whe you do moderate activities for at least 10 miutes at a time, how much total time do you sped doig these activities? Hours Ad miutes Refused Now, thikig about the vigorous activities you do whe you are ot workig at a paid job: NOTE: EMPHASIZE VIGOROUS 7. I a usual week, do you do vigorous activities for at least 10 miutes at a time, such as ruig, aerobics, heavy yard work, or aythig else that causes large icreases i breathig or heart rate? 1 Yes 2 No {GO TO Q7} : 7777 Do t kow/not sure {GO TO Q7} 9999 Refused {GO TO Q7} 8. O how may days per week do you do these vigorous activities for at least 10 miutes at a time? days 9999 Refused {GO TO Q7} 9. O days whe you do vigorous activities for at least 10 miutes at a time, how much total time do you sped doig these activities? Hours Ad miutes 9999 Refused