title: Factor analysis findings for the NDI.
authors.forename: Charles Philip
authors.initials: CP
authors.lastname: Gabel
authors.forename: Markus
authors.initials: M
authors.lastname: Melloh
authors.forename: Brendan
authors.initials: B
authors.lastname: Burkett
mesh_terms: D006801:Humans; D019547:Neck Pain / Q000175:diagnosis* / Q000503:physiopathology; D010147:Pain Measurement / Q000379:methods*; D025341:Principal Component Analysis / Q000379:methods*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires