Methodology National Sports Survey SUMMARY

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1 Methodology 017 Natioal Sports Survey Prepared by Priceto Survey Research Associates Iteratioal for the Washigto Post ad the Uiversity of Massachusetts Lowell August 017 SUMMARY The 017 Natioal Sports Survey obtaied telephoe iterviews with a atioally represetative sample of 1,000 adults, age 18 or older, livig i the cotietal Uited States. Telephoe iterviews were coducted by ladlie (344) ad cell phoe (656, icludig 398 without a ladlie phoe). The survey was coducted by Priceto Survey Research Associates Iteratioal (PSRAI). Iterviews were doe i Eglish ad Spaish by Issues & Aswers Network, Ic. from August 14 to 1, 017. Statistical results are weighted to correct kow demographic discrepacies. The margi of samplig error for the complete set of weighted data is ± 3.7 percetage poits. Details o the desig, executio ad aalysis of the survey are discussed below. DESIGN AND DATA COLLECTION PROCEDURES Sample Desig A combiatio of ladlie ad cellular radom digit dial (RDD) samples was used to represet all adults i the cotietal Uited States who have access to either a ladlie or cellular telephoe. Both samples were provided by Survey Samplig Iteratioal, LLC (SSI) accordig to PSRAI specificatios. Numbers for the ladlie sample were draw with equal probabilities from active blocks (area code + exchage + two-digit block umber) that cotaied oe or more residetial directory listigs. The cellular sample was ot list-assisted, but was draw through a systematic samplig from dedicated wireless 100-blocks ad shared service 100-blocks with o directory-listed ladlie umbers.

2 Cotact Procedures Iterviews were coducted from August 14 to 1, 017. As may as five attempts were made to cotact every sampled telephoe umber. Sample was released for iterviewig i replicates, which are represetative subsamples of the larger sample. Usig replicates to cotrol the release of sample esures that complete call procedures are followed for the etire sample. Calls were staggered over times of day ad days of the week to maximize the chace of makig cotact with potetial respodets. Each phoe umber received at least oe daytime call whe ecessary. For the ladlie sample, iterviewers asked to speak with the yougest adult male or female curretly at home based o a radom rotatio. If o male/female was available, iterviewers asked to speak with the yougest adult of the other geder. This systematic respodet selectio techique has bee show to produce samples that closely mirror the populatio i terms of age ad geder whe combied with cell iterviewig. Prior to dialig, the ladlie sample was scrubbed of o-workig umbers. Additioally, the ladlie sample was also scrubbed of umbers that have bee ported to wireless service by comparig the sample file to the most recetly available Itermodal Ported Telephoe Number Idetificatio Service database. For the cellular sample, iterviews were coducted with the perso who aswered the phoe. Iterviewers verified that the perso was a adult ad i a safe place before admiisterig the survey. WEIGHTING AND ANALYSIS Weightig is geerally used i survey aalysis to compesate for sample desigs ad patters of o-respose that might bias results. The sample was weighted to match atioal adult geeral populatio parameters. A two-stage weightig procedure was used to weight this dual-frame sample. The first stage of weightig corrected for differet probabilities of selectio associated with the umber of adults i each household ad each respodet s telephoe usage patters. 1 This weightig also adjusts for the overlappig ladlie ad cell sample frames ad the relative sizes of each frame ad each sample. 1 i.e., whether respodets have oly a ladlie telephoe, oly a cell phoe, or both kids of telephoe.

3 This first-stage weight for the i th case ca be expressed as: WT i = [( S LL 1 LL F LL AD i ) + ( S CP CP i F i ) ( S LL 1 LL CP F LL AD i S 1 CP CP i F i )] CP Where SLL = the size of the ladlie sample FLL = the size of the ladlie sample frame SCP = the size of the cell sample FCP = the size of the cell sample frame ADi = Number of adults i household i LLi=1 if respodet has a ladlie phoe, otherwise LL=0. CPi=1 if respodet has a cell phoe, otherwise CP=0. The secod stage of weightig balaced sample demographics to populatio parameters. The sample was balaced by form to match atioal populatio parameters for sex, age, educatio, race, Hispaic origi, regio (U.S. Cesus defiitios), populatio desity, ad telephoe usage. The basic weightig parameters came from the U.S. Cesus Bureau s 015 America Commuity Survey (ACS) data. The populatio desity parameter was derived from Cesus 010 data. The telephoe usage parameter came from a aalysis of the July-December 016 Natioal Health Iterview Survey. 3 Weightig was accomplished usig SPSSINC RAKE, a SPSS extesio module that simultaeously balaces the distributios of all variables usig the GENLOG procedure. Weights were trimmed to prevet idividual iterviews from havig too much ifluece o the fial results. The use of these weights i statistical aalysis esures that the demographic characteristics of the sample closely approximate the demographic characteristics of the atioal populatio. Table 1 compares weighted ad uweighted sample distributios to populatio parameters. ACS aalysis was based o all adults excludig those livig i istitutioal group quarters. 3 Blumberg SJ, Luke JV. Wireless substitutio: Early release of estimates from the Natioal Health Iterview Survey, July- December, 016. Natioal Ceter for Health Statistics. May

4 Table 1: Sample Demographics Parameter Uweighted Weighted Geder Male 48.3% 56.5% 49.8% Female 51.7% 43.5% 50.% Age % 9.0% 1.3% % 1.% 17.0% % 18.5% 16.8% % 15.% 17.% % 17.0% 16.9% % 8.1% 19.8% Educatio HS Graduate or Less 40.3% 7.3% 39.5% Some College/Assoc. Degree 31.3% 9.% 31.0% College Graduate 8.4% 43.5% 9.5% Race/Ethicity White/ot Hispaic 64.8% 75.6% 66.0% Black/ot Hispaic 11.8% 9.6% 11.5% Hispaic 15.5% 9.3% 14.7% Other/ot Hispaic 7.9% 5.5% 7.8% Regio Northeast 18.1% 17.7% 18.% Midwest 1.% 0.5% 1.3% South 37.7% 38.1% 37.5% West 3.0% 3.7% 3.1% Couty Pop. Desity 1 - Lowest 19.9% 0.3% 0.1% 0.0% 1.5% 0.0% 3 0.1% 0.8% 0.4% 4 0.0% 19.1% 19.8% 5 - Highest 0.0% 18.3% 19.8% Household Phoe Use LLO 5.3% 4.6% 5.0% Dual 41.% 55.6% 4.3% CPO 53.5% 39.8% 5.7% 4

5 Effects of Sample Desig o Statistical Iferece Post-data collectio statistical adjustmets require aalysis procedures that reflect departures from simple radom samplig. PSRAI calculates the effects of these desig features so that a appropriate adjustmet ca be icorporated ito tests of statistical sigificace whe usig these data. The so-called "desig effect" or deff represets the loss i statistical efficiecy that results from uequal weights. The total sample desig effect for this survey is weight, wi as: PSRAI calculates the composite desig effect for a sample of size, with each case havig a deff i1 i1 w w i i formula 1 I a wide rage of situatios, the adjusted stadard error of a statistic should be calculated by multiplyig the usual formula by the square root of the desig effect ( deff ). Thus, the formula for computig the 95% cofidece iterval aroud a percetage is: pˆ deff 1.96 pˆ(1 pˆ) formula where pˆ is the sample estimate ad is the uweighted umber of sample cases i the group beig cosidered. The survey s margi of error is the largest 95% cofidece iterval for ay estimated proportio based o the total sample -- the oe aroud 50%. For example, the margi of error for the etire sample is ±3.7 percetage poits. This meas that i 95 out every 100 samples draw usig the same methodology, estimated proportios based o the etire sample will be o more tha 3.7 percetage poits away from their true values i the populatio. The margi of error for estimates based o form 1 sports fas 4 (N=410) is ±5.8 percetage poits. For results based o form sports fas (N=403), the margi of error is ±5.7 percetage poits. It is importat to remember that samplig fluctuatios are oly oe possible source of error i a survey estimate. Other sources, such as respodet selectio bias, 4 Sports fas are respodets who described themselves as a avid, regular or casual sports fa. 5

6 questioaire wordig ad reportig iaccuracy, may cotribute additioal error of greater or lesser magitude. RESPONSE RATE Table reports the dispositio of all sampled telephoe umbers ever dialed from the origial telephoe umber samples. The respose rate estimates the fractio of all eligible sample that was ultimately iterviewed. Respose rates are computed accordig to America Associatio for Public Opiio Research stadards. 5 Thus the respose rate for the ladlie samples was percet. The respose rate for the cellular samples was 4 percet. 5 America Associatio for Public Opiio Research Stadard Defiitios: Fial Dispositios of Case Codes ad Outcome Rates for Surveys. 9th editio. AAPOR. 6

7 Table. Sample Dispositio Ladlie Cell 1, No-residetial/Busiess (4.500),859 0 Ported umbers idetified before dialig (4.40) 1 0 Cell i ladlie frame (4.40) 4, OF = Out of Frame 3,406 11,08 Not workig (4.300) 50,369 0 Screeed ladlie discoects removed prior to dialig Computer/fax/modem (4.00) 54,575 11,40 NWC = Not workig/computer 4,67 3,33 NA/Busy all attempts (3.10, 3.130) 49,948 8,079 UHUONC = No-cotact, ukow if household/ukow other 5,13 10,771 Voice mail (3.140) 0 0 Other o-cotact (deaf/disabled/deceased) (3.11) 5,13 10,771 UONC = No-cotact, ukow eligibility,695 4,586 Refusals (3.11) 568 1,46 Callbacks (INCLUDE Spaish CBs) (3.11) 3,63 6,048 UOR = Refusal, ukow if eligible O = Other (laguage) (3.11) Child's cell phoe (4.700) 19 0 Other ieligible (4.700) SO = Scree out 44 R = Refusal, kow eligible (breakoffs ad qualified CBs) (.100) I = Completed iterviews (1.0) 117,530 38,01 T = Total umbers sampled 13.3% 60.7% e1 = (I+R+SO+O+UOR+UONC)/(I+R+SO+O+UOR+UONC+OF+NWC) - Est. frame eligibility of ocotacts 95.1% 68.9% e = (I+R)/(I+R+SO) - Est. screeig eligibility of uscreeed cotacts 4.1% 3.1% CON = [I + R + (e*[o + UOR])]/[I + R + (e*[o + UOR + UONC]) + (e1*e*uhuonc)] 9.6% 1.9% COOP = I/[I + R + (e*[o + UOR])].3% 4.1% AAPOR RR3=I/[I+R+[e*(UO R+UO NC+O)]+[e1*e*UHUO NC]] = CON*COOP 7