Self administered cognitive screening test (TYM) for detection of Alzheimer's disease: cross sectional study

BMJ. 2009 Jun 9;338:b2030. doi: 10.1136/bmj.b2030.

Abstract

Objective: To evaluate a cognitive test, the TYM ("test your memory"), in the detection of Alzheimer's disease.

Design: Cross sectional study.

Setting: Outpatient departments in three hospitals, including a memory clinic.

Participants: 540 control participants aged 18-95 and 139 patients attending a memory clinic with dementia/amnestic mild cognitive impairment.

Intervention: Cognitive test designed to use minimal operator time and to be suitable for non-specialist use.

Main outcome measures: Performance of normal controls on the TYM. Performance of patients with Alzheimer's disease on the TYM compared with age matched controls. Validation of the TYM with two standard tests (the mini-mental state examination (MMSE) and the Addenbrooke's cognitive examination-revised (ACE-R)). Sensitivity and specificity of the TYM in the detection of Alzheimer's disease.

Results: Control participants completed the TYM with an average score of 47/50. Patients with Alzheimer's disease scored an average of 33/50. The TYM score shows excellent correlation with the two standard tests. A score of <or=42/50 had a sensitivity of 93% and specificity of 86% in the diagnosis of Alzheimer's disease. The TYM was more sensitive in detection of Alzheimer's disease than the mini-mental examination, detecting 93% of patients compared with 52% for the mini-mental state exxamination. The negative and positive predictive values of the TYM with the cut off of <or=42 were 99% and 42% with a prevalence of Alzheimer's disease of 10%. Thirty one patients with non-Alzheimer dementias scored an average of 39/50.

Conclusions: The TYM can be completed quickly and accurately by normal controls. It is a powerful and valid screening test for the detection of Alzheimer's disease.

Publication types

  • Evaluation Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / diagnosis*
  • Ambulatory Care
  • Case-Control Studies
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Memory Disorders / diagnosis*
  • Neuropsychological Tests
  • Observer Variation
  • ROC Curve
  • Self Care
  • Sensitivity and Specificity