ABSTRACT
Objectives: Dementia-specific anxiety scales in the Norwegian language are lacking; the aim of this study was to investigate the validity and inter-rater reliability of a Norwegian version of the Rating Anxiety in Dementia (RAID-N) scale.
Method: The validity of the RAID-N was tested in a sample of 101 patients with dementia from seven Norwegian nursing homes. One psychogeriatrician (n = 50) or a physician with long experience with nursing home patients (n = 51) ‘blind’ to the RAID-N score diagnosed anxiety according to DSM-5 criteria of generalised anxiety disorder (GAD). A receiver operating characteristic (ROC) analysis assessed the best cut-off point for the RAID-N, and the area under the curve (AUC) was calculated. Inter-rater reliability was tested in a subgroup of 53 patients by intraclass correlation (ICC) and Cohen's kappa.
Results: Twenty-eight of 101 (27.7%) met the GAD criteria. The mean RAID-N score for patients with GAD was 16.1 (SD 6.3) and without GAD, 8.8 (SD 6.5) (p < 0.001). A cut-off score of ≥12 on the RAID-N gave a sensitivity of 82.1%, specificity of 70.0%, and 73.3% accuracy in identifying clinically significant GAD in patients with dementia. Inter-rater reliability on overall RAID-N items was good (ICC = 0.82), Cohen's kappa was 0.58 for total RAID-N score, with satisfactory internal consistency (Cronbach's alpha = 0.81).
Conclusion: The RAID-N has fairly good validity and inter-rater reliability, and could be useful to assess GAD in patients with dementia. Further studies should investigate the optimal RAID-N cut-off score in different settings.
Acknowledgments
We would like to thank all the participants and the staff members of the nursing homes for their participation and cooperation in the study. A warm thank to the RAID-N validation study group, and Merete Andreassen who helped in data scanning. The study was supported by and conducted at the Centre of Old Age Psychiatry Research, Innlandet Hospital Trust, and the Norwegian National Advisory Unit on Ageing and Health, Vestfold Hospital Trust.
RAID-N validation study group: Olav Aga (retired physician-in-chief), Oskar Sommer, Susan Juell, Bjørn Lichtwark (Psychogeriatri, Centre of Old Age Psychiatry Research, Innlandet Hospital Trust), Kjersti Thomassen (Solberglia Nursing Home and Activity Centre, Nedre Eiker), and Hege Dalsveen (Section of Old Age Psychiatry, Vestre Viken Hospital Trust).
Disclosure statement
No potential conflict of interest was reported by the authors.