Assessment Tools: Abnormal involuntary Movement Scale (AIMS)
The AIMS is a widely used instrument developed by the Psychopharmacology Research Branch of the National Institute of Mental Health. AIMS is administered at a baseline before the institution of pharmacotherapy to document any movements present, then at least three months after that during treatment (Wheeler, 2014). Part of the AIMS assessment includes observation of the patients when they are distracted by other activities. Patients may suppress movements while concentrating intensely
Psychometric Properties of the AIMS
Psychometrics is the construction and validation of measurement instruments and assessing if these instruments are reliable and valid forms of measurement. A reliable scale consistently measures the same construct and occurs across testing sessions, individuals, and settings. A valid measure measures what it says it is going to measure. Their psychometric properties limit the usefulness of clinical scales. In terms of clinical utility, AIMS is a 12-item anchored scale administered by a clinician and scored. The first ten items are rated on a 5 point scale with 1-4 items assessing the orofacial movement, 5-7 dealing with extremity and truncal dyskinesia, 8-10 dealing with global severity. Items 11-12 are yes-no questions concerning teeth and denture since such issues can lead to a mistaken diagnosis of dyskinesia (Stacy et al., 2019). However, the instrument has some shortcomings. Instructions and refinements for the global and distress measures (items 8–10) and dental pathology (items 11–12) have not been standardized. Also, items 9 and 10 have not correlated with responses on the anatomic measures of severity of TD (items 1–7) and may not be reliable given the lack of awareness and insight reported by some patients (Stacy et al., 2019)
Appropriate Use of the AIMS
The AIMS can be used in both research and clinical settings and administered by any health care professional with appropriate training. The tool is recommended for patients receiving treatment with substances that may cause Tardive Dyskinesia (TD). As an instrument that measures the frequency, amplitude, distribution, and persistence of abnormal movements, the AIMS can be administered to any patient regardless of psychiatric diagnosis. From a clinical and patient or caregiver perspective, however, the patient’s diagnosis (e.g., schizophrenia or mood disorder), level of functioning, and psychiatric stability may be essential factors in determining the overall functional significance of TD in terms of impact on the quality of life. For example, an individual with stable bipolar disorder and high psychosocial functioning could have a rating of 2 (mild) in a single AIMS item, such as the tongue. In a clinical trial in which efficacy is being evaluated and averaged within a group of participants (rather than in an individual patient), this rating would equal a total score of 2 and might be considered a “low” overall score and would not even meet research diagnostic criteria (Wheeler, 2014).
Similar to its use in clinical trials, the AIMS examination, and rating scores can be used in clinical practice to document the emergence of medication-induced TD and monitor changes in TD severity over time. To this end, formal guidelines have been developed that propose administrating the AIMS at regular intervals in patients receiving antipsychotics in clinical settings. A more conservative approach in clinical practice may be for all patients and their caregivers to be informed about regular self-examination and to be questioned and briefly examined for abnormal movements at every clinic visit (Kane et al., 2018).
References
Kane, J. M., Correll, C. U., Nierenberg, A. A., Caroff, S. N., Sajatovic, M., & Tardive Dyskinesia Assessment Working Group. (2018). Revisiting the abnormal involuntary movement scale: proceedings from the tardive dyskinesia assessment workshop. The Journal of clinical psychiatry, 79(3), 0-0.
Stacy, M., Sajatovic, M., Kane, J. M., Cutler, A. J., Liang, G. S., O’Brien, C. F., & Correll, C. U. (2019). Abnormal involuntary movement scale in tardive dyskinesia: Minimal clinically significant difference. Movement Disorders, 34(8), 1203-1209.
Wheeler, K. (Ed.). (2014). Psychotherapy for the advanced practice psychiatric nurse: A how-to guide for evidence-based practice (2nd ed.). New York, NY: Springer Publishing Company.