SURVEYDESIGNANDMETHODS RESPONSERATE After determiningtherequiredsamplefromU.S.CensusBureaudata,Kaiser/HRETdrewitssamplefromaSurveySampling Incorporatedlist(basedonanoriginalDunandBradstreetlist)ofthenation’sprivateemployersandfromtheCensusBureau’s CensusofGovernmentslistofpublicemployerswiththreeormoreworkers. Toincreaseprecision,Kaiser/HRETstratifiedthe samplebytenindustrycategoriesandsixsizecategories. Kaiser/HRETattemptedtorepeatinterviewswithprioryears’survey respondents(withatleasttenemployees)whoparticipatedineitherthe2015orthe2016survey,orboth. Firmswith3-9 employeesarenotincludedinthepaneltominimizetheimpactofpaneleffectsontheofferratestatistic. Asaresult,1,427 6 of the 2,137 firmsthatcompletedthefullsurveyalsoparticipatedineitherthe2015or2016surveys,orboth. Theoverall 7 responserateis33%. ResponseratesarecalculatedusingaCASROmethod,whichaccountsforfirmsthataredetermined tobeineligibleinitscalculation. Beginningin2012,thecalculationoftheresponserateswasadjustedtobeslightlymore conservativethanpreviousyears. WhiletheKaiser/HRETsurveysimilartootheremployerandhouseholdsurveyshasseenageneraldecreaseinresponserates overtime,thedecreasebetweenthe2016and2017responseratesisnotsolelyexplainedbythistrend. Inordertoimprove statistical power amongsub-groups,includingsmallfirmsandthosewithahighshareoflowincomeworkers,thesizeofthe samplewasexpandedfrom5,732in2016to7,895in2017. Asaresult,the2017surveyincludes204morecompletesthanthe 2016survey. Whilethisgenerallyincreasestheprecisionofestimates(forexample,areductioninthestandarderrorforthe offerratefrom2.2%to1.8%),ithastheeffectofreducingtheresponserate. In2017,non-panelfirmshadaresponserateof 17%,comparedto62%forfirmsthathadparticipatedinoneofthelasttwoyears. Toincreaseresponserates,firmswith3-9employeeswereofferedanincentiveforparticipatinginthesurvey. Athirdofthese firmsweresenta$5Starbucksgiftcardintheadvanceletter,athirdwereofferedanincentiveof$50incashorasadonationto acharityoftheirchoiceaftercompletingthefullsurvey,andathirdoffirmswereofferednoincentiveatall. Ouranalysisdoes notshowsignificantdifferencesinresponsestokeyvariablesamongtheseincentivegroups. 6 In total, 139 firms participated in 2015, 274 firms participated in 2016, and 1,014 firms participated in both 2015 and 2016. 7 Responserateestimatesarecalculatedbydividingthenumberofcompletesoverthenumberofrefusalsandthefractionofthefirmswithunknowneligibility toparticipateestimatedtobeeligible. Firmsdeterminedtobeineligibletocompletethesurveyarenotincludedintheresponseratecalculation. The Kaiser Family Foundation and Health Research & Educational Trust / Page 17