Two assessments to evaluate imagery ability: translation, test-retest reliability and concurrent validity of the German KVIQ and Imaprax

Schuster et al. BMC Medical Research Methodology 2012, 12:127 http://www.biomedcentral.com/1471-2288/12/127 RESEARCH ARTICLE Open Access Two assessments to evaluate imagery ability: translation, test-retest reliability and concurrent validity of the German KVIQ and Imaprax Corina Schuster1,2*, Anina Lussi3, Brigitte Wirth4 and Thierry Ettlin1,5 Abstract Background: A combination of physical practice and motor imagery (MI) can improve motor function. It is essential to assess MI vividness in patients with sensorimotor impairments before implementing MI interventions. The study's aims were to translate the Canadian Kinaesthetic and Visual Imagery Questionnaire (KVIQ) and the French Imaprax, and to examine reliability and validity of the German versions. Methods: Questionnaires were translated according to guidelines. With examiner’s help patients (diagnosis: stroke: subacute/chronic, brain tumour, Multiple Sclerosis, Parkinson’s disease) were tested twice within seven days (T0, T1). KVIQ-G: Patients were shown a movement by the examiner, before executing and imagining the movement. They rated vividness of the image and intensity of the sensations on a five-point Likert-scale. Imaprax required a 3-step procedure: imagination of one of six gestures; evaluation of gesture understanding, vividness, and imagery perspective. Questionnaire data were analysed overall and for each group. Reliability parameters were calculated: intraclass correlation coefficient (ICC), Cronbach's alpha, standard error of measurement, minimal detectable change. Validity parameters included Spearman's rank correlation coefficient and factor analysis of the KVIQ-G-20. Results: Patients (N = 73, 28 females, age: 63 ± 13) showed the following at T0: KVIQ-G-20vis 41.7 ± 9, KVIQ-G-10vis 21.1 ± 5. ICC for KVIQ-G-20vis and KVIQ-G-10vis was 0.77; KVIQ-G-20kin 36.4 ± 12, KVIQ-G-10kin 18.3 ± 6. ICCs for KVIQ-G-20kin and KVIQ-G-10kin were 0.83/0.85; Imapraxvis 32.7 ± 4 and ICC 0.51. Internal consistency was estimated for KVIQ-G-20 αvis = 0.94/αkin = 0.92, KVIQ-G-10 αvis = 0.88/αkin = 0.96, Imaprax-G αvis = 0.70. Validity testing was performed with 19 of 73 patients, who chose an internal perspective: rs = 0.36 (p = 0.13). Factor analysis revealed two factors correlating with r = 0.36. Both explain 69.7% of total variance. Conclusions: KVIQ-G and Imaprax-G are reliable instruments to assess MI in patients with sensorimotor impairments confirmed by a KVIQ-G-factor analysis. KVIQ-G visual values were higher than kinaesthetic values. Patients with Multiple Sclerosis showed the lowest, subacute stroke patients the highest values. Hemiparetic patients scored lower in both KVIQ-G subscales on affected side compared to non-affected side. It is suggested to administer the Imaprax-G before the KVIQ-G to test patient’s ability to distinguish between external and internal MI perspective. Duration of both questionnaires lead to an educational effect. Imaprax validity testing should be repeated. * Correspondence: 1 Reha Rheinfelden, Salinenstrasse 98, Rheinfelden 4310, Switzerland 2 Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, United Kingdom Full list of author information is available at the end of the article © 2012 Schuster et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Schuster et al. BMC Medical Research Methodology 2012, 12:127 http://www.biomedcentral.com/1471-2288/12/127 Background Motor imagery (MI) has been defined as a dynamic state during which the representation of a given motor act is internally rehearsed without motor output by Decety and Grezès in 1999 [1]. It has been shown to be beneficial in motor function recovery for patients after a lesion of the central nervous system (CNS) if MI is added to physical practice (PP). Positive effects of MI have been summarised in several literature reviews [2,3]. To determine participant benefits of MI, it is important to evaluate MI vividness and its changes during a MI intervention period. In a recent literature review MI interventions have been evaluated regarding their MI training session elements and temporal parameters to determine successful MI interventions [4]. Only 41 out of the 141 MI interventions used one or more assessments to evaluate participants’ imagery ability. In particular, in Medicine MI assessments have been used in 11 out of 37 MI interventions. Out of the 11 MI interventions nine were performed with patients after a central lesion, e.g. stroke. Three of the nine MI interventions used the Movement Imagery Questionnaire (MIQ) [5,6] or the Revised Movement Imagery Questionnaire (MIQ-R) [7]. Others used custom-made imagery questionnaires or the Kinesthetic and Visual Imagery Questionnaire (KVIQ) [8]. Both assessments (MIQ and KVIQ) aim to assess MI vividness for motor performance. The MIQ includes 18 items to imagine with different levels of movements, e.g. standing on one leg, jumping straight up in the air, or moving the extended arm. Furthermore, all items have to be imagined using two imagery types: visual MI (9 items) and kinaesthetic MI (9 items). All items are rated on a 7point scale with 1 representing the lowest quality of seeing or feeling the movement. Hall and Martin (1997) developed the MIQ for healthy participants [9]. Therefore, movements to be imagined in the MIQ do not consider patient condition, e.g. a stroke patient with a hemiparesis would be asked to imagine her/ himself jumping straight up in the air. Malouin and colleagues (2007) developed the KVIQ specifically to address participants with sensorimotor impairments [8]. In particular, KVIQ has been evaluated in patients after stroke, with a lower limb amputation, with an acquired blindness, lower limb immobilisation, and Parkinson’s disease [8,10]. Participants are asked to imagine movements of the dominant and non-dominant body side from the internal perspective. Imagination is once performed using visual MI to see, and once using kinaesthetic MI to feel the movement. Imagined movements include all four limbs and the whole body. All movements are imagined to be performed in a sitting position and in one joint axis. If patients cannot perform the required movement, the examiner will assist to move the patient’s limb or will move it passively. Page 2 of 13 The two main differences between KVIQ and MIQ are administration and the selection of the movements to be imagined. Whereas the MIQ is self-administered and focuses on complex high-level body movements, the KVIQ requires an examiner to be present, giving the instructions, performing example movements, and filling in the scoring sheet. The KVIQ focuses on simple, one joint axis movements of the upper and lower limbs, head, and trun (...truncated)