title: Validation of the Headache Impact Test (HIT-6™) across episodic and chronic migraine.
abstract: OBJECTIVE
  The purpose of this study was to assess psychometric properties of the six-item Headache Impact Text (HIT-6™) across episodic and chronic migraine.
  
  
  METHODS
  Using a migraine screener and number of headache days per month (HDPM), participants from the National Survey of Headache Impact (NSHI) study and the HIT-6 validation study (HIT6-V) were selected for this study. Eligible participants were categorized into three groups: chronic migraine (CM: ≥ 15 HDPM); episodic migraine (EM: < 15 HDPM); non-migraine headaches. Reliability and validity of the HIT-6 were evaluated.
  
  
  RESULTS
  A total of 2,049 survey participants met the inclusion/exclusion criteria for this study. Participants were identified as 6.4% CM; 42.1% EM; 51.5% non-migraine, with respective mean HIT-6 scores: 62.5 ± 7.8; 60.2 ± 6.8; and 49.1 ± 8.7. High reliability was demonstrated with internal consistency (time1/time2) of 0.83/0.87 in NSHI, and 0.82/0.92 in HIT6-V. Intra-class correlation for test-retest reliability was very good at 0.77. HIT-6 scores correlated significantly (p < .0001) with total Migraine Disability Assessment Scale scores (r = 0.56), headache pain severity (r = 0.46), and HDPM (r = 0.29). Discriminant validity analysis showed significantly different HIT-6 scores (F = 488.02, p < .0001) across the groups.
  
  
  CONCLUSIONS
  Results from these analyses confirm that the HIT-6 is a reliable and valid tool for discriminating headache impact across episodic and chronic migraine.
authors.affiliation: QualityMetric, Inc., 24 Albion Road, Lincoln, RI 02865-4207, USA. myang@analysisgroup.com
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Regina
authors.initials: R
authors.lastname: Rendas-Baum
authors.forename: Sepideh F
authors.initials: SF
authors.lastname: Varon
authors.forename: Mark
authors.initials: M
authors.lastname: Kosinski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D017281:Cost of Illness; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000523:psychology*; D011594:Psychometrics / Q000379:methods*; D011788:Quality of Life; D015203:Reproducibility of Results; D055815:Young Adult
references.citation: Neurology. 2003 Aug 12;61(3):375-82
references.pmid: 12913201
references.citation: Headache. 2003 Nov-Dec;43(10):1049-59
references.pmid: 14629240
references.citation: Cephalalgia. 2006 Jun;26(6):742-6
references.pmid: 16686915
references.citation: Qual Life Res. 2003 Dec;12(8):963-74
references.pmid: 14651415
references.citation: Headache. 2003 Apr;43(4):336-42
references.pmid: 12656704
references.citation: Psychol Bull. 1979 Mar;86(2):420-8
references.pmid: 18839484
references.citation: Med Care. 2000 Sep;38(9 Suppl):II73-82
references.pmid: 10982092
references.citation: J Clin Neurol. 2008 Dec;4(4):158-63
references.pmid: 19513291
references.citation: Neurology. 2007 Jan 30;68(5):343-9
references.pmid: 17261680
references.citation: CNS Drugs. 2006;20 Spec no.1:24-36
references.pmid: 16841524
references.citation: Biometrics. 1990 Dec;46(4):1171-8
references.pmid: 2085632
references.citation: Cephalalgia. 2008 May;28(5):484-95
references.pmid: 18294250
references.citation: Neurology. 2008 Sep 9;71(11):848-55
references.pmid: 18779513
references.citation: Cephalalgia. 2005 Mar;25(3):184-90
references.pmid: 15689193
references.citation: Cephalalgia. 2007 Jul;27(7):814-23
references.pmid: 17441971
references.citation: Eur J Neurol. 2005 Mar;12(3):189-93
references.pmid: 15693807
references.citation: Cephalalgia. 2000 Nov;20(9):765-86
references.pmid: 11167908
references.citation: Headache. 2007 Jan;47(1):65-72
references.pmid: 17355496
references.citation: Headache. 2008 Jan;48(1):7-15
references.pmid: 18184280
references.citation: Cephalalgia. 2006 May;26(5):578-88
references.pmid: 16674767
references.citation: Headache. 2001 Jul-Aug;41(7):638-45
references.pmid: 11554951
references.citation: Lancet Neurol. 2006 Feb;5(2):148-157
references.pmid: 16426991
references.citation: J Clin Epidemiol. 2006 Apr;59(4):374-80
references.pmid: 16549259
references.citation: Headache. 2005 May;45(5):429-37
references.pmid: 15953259
references.citation: Neurology. 1994 May;44(5):837-42
references.pmid: 8190284
references.citation: Headache. 2009 Apr;49(4):498-508
references.pmid: 19245386
references.citation: Pain. 2003 Dec;106(3):337-345
references.pmid: 14659516
references.citation: Biomed Pharmacother. 1995;49(10):452-5
references.pmid: 8746071
references.citation: Headache. 2008 Jan;48(1):58-66
references.pmid: 18184287
references.citation: Cephalalgia. 2008 Jan;28(1):26-34
references.pmid: 17970768
references.citation: Cephalalgia. 2003 Jul;23(6):441-50
references.pmid: 12807523
references.citation: Neurology. 2008 Aug 19;71(8):559-66
references.pmid: 18711108
references.citation: Headache. 2008 Jun;48(6):900-13
references.pmid: 18047501
references.citation: Cephalalgia. 1998 Nov;18(9):638-43
references.pmid: 9876889
references.citation: Cephalalgia. 1996 Jun;16(4):231-8; discussion 215
references.pmid: 8792034
references.citation: Neurology. 2001;56(6 Suppl 1):S20-8
references.pmid: 11294956
references.citation: Qual Life Res. 2003 Dec;12(8):981-1002
references.pmid: 14651417
references.citation: Headache. 2010 Mar;50(3):383-95
references.pmid: 19817883
references.citation: Cephalalgia. 2004;24 Suppl 1:9-160
references.pmid: 14979299
references.citation: Headache. 2005 Jun;45(6):638-43
references.pmid: 15953295
references.citation: Cephalalgia. 2007 Dec;27(12):1386-97
references.pmid: 17888013