Date Published: July 30, 2018
Publisher: Springer International Publishing
Author(s): Karolina Piotrowicz, Wojciech Romanik, Anna Skalska, Barbara Gryglewska, Katarzyna Szczerbińska, Jarosław Derejczyk, Roger M. Krzyżewski, Tomasz Grodzicki, Jerzy Gąsowski.
Since its introduction by Hodkinson in 1972, Abbreviated Mental Test Score (AMTS) and its English and other language versions have been widely used in research and clinical practice alike. However, whether the various versions of AMTS yield equivalent information has never been tested.
We performed cross-sectional assessment of inpatients aged 65+ years with seven AMTS versions and the Mini-Mental State Examination (MMSE) after correction for age and education (MMSEc). We used the MMSEc cut-off score of < 24 as comparator and fitted linear regression models from which we obtained the receiver operating characteristics, and further compared the c-statistics obtained for each version of AMTS. We used Spearman’s correlation to check the relation between different AMTS versions. The mean (SD) age of 72 (52.8% women) patients was 76.2 (7.6) years. The average time spent on education was 11.3 (3.5) years. The AMTS score across versions varied between 7.4 (2.0) and 8.2 (1.7). The MMSE averaged 24.1 (4.6) and the MMSEc averaged 25.2 (4.1). We found that the c-statistic across AMTS versions with dichotomised MMSEc as comparator ranged from 0.83 to 0.85 and did not significantly differ from the c-statistic of 0.87 for original AMTS (all p > 0.16). We found AMTS versions to be significantly correlated (all r between 0.83 and 0.99, all p < 0.0001). We found AMTS to be a reliable and useful tool in the screening for possible cognitive impairment. This seems to be true irrespective of whether we use the original test or any of its studied modifications.
The Abbreviated Mental Test Score (AMTS) was first introduced in 1972 by Hodkinson for the assessment of mental impairment in old age . AMTS is a 10-item screening questionnaire that included in the original version questions about: subject’s age, date of birth, the current time and year, the name of hospital, the name of the present British monarch, the year of the beginning of the First World War; and a recall of a previously given address, counting backwards by 1, from 20 to 1, and recognition of two persons (e.g., doctor, nurse, etc.) .
The aim of the study was to compare the basic diagnostic properties of the Polish translation , the English versions published in the Occasional Paper by the Royal College of General Practitioners (RCGP) [3, 4], and the original questionnaire of the Abbreviated Mental Test Score [1, 2]. We employed the Mini-Mental State Examination (MMSE) after correction for age and years of education (MMSEc), as a reference test for suspicion of cognitive impairment, with the MMSEc cut-off score of 24 points (23 or below) . To adjust the results for age and education we used the correction as proposed by Mungas et al. . The threshold score for the cognitive impairment in AMTS was 7 points (6 or below). The comparison of the questionnaires of the original, the Polish version and the English language derivatives of the original AMTS is presented in Table 1. When testing the ability to recognise persons, in the RCGP version of AMTS we used the pictures of a postman and a cook, and the Pope John Paul II and the Queen Elizabeth II. Additionally, we decided to adapt the RCGP version for the Polish clinical environment, and proposed to use a picture of Lech Wałęsa, the first democratically elected president of Poland since the fall of the East Bloc, instead of a picture of the Queen. The study was performed with the approval of the Ethics Committee of the Jagiellonian University, Kraków, Poland (No.: 122.6120.191.2016), and all subjects gave their informed consent to take part in it. All versions of AMTS were translated and back-translated, as applicable, between the English and the Polish by separate members of the research team (KP, JG). We used the validated Polish version of the MMSE . The eligible subjects had to be aged 65 years or more, and they had to be free from an acute disease. The included patients were the inpatients of Dept. of Internal Medicine and Geriatrics, University Hospital, Kraków, Poland or the patients under assessment for planned surgical procedure at the Central Teaching Hospital, Medical University of Warsaw, Warsaw, Poland. The acutely admitted patients were assessed after stabilization of their medical condition.
We collected data of 72 consecutive patients (52.8% women) aged 65 years and older with mean (SD) age of 76.2 (7.6) years, and 11.3 (3.5) years of formal education. The MMSE averaged 24.1 (4.6) and the MMSEc averaged 25.2 (4.1). Based on the unadjusted MMSE results, 38.7% of the subjects had the suspicion of cognitive impairment. After the correction for age and years of education  the percentage of subjects with the MMSE < 24 was 26.0%. The AMTS score across versions varied between 7.4 (2.0) and 8.2 (1.7). Based on the AMTS, the suspicion of cognitive impairment ranged from 12.3 to 21.9%. The inter-version AMTS correlations ranged from 0.83 to 0.99 (all p < 0.0001). The concordances (AUC) between studied AMTS versions and the classification of patients based on MMSEc ranged from 0.83 to 0.87 and did not significantly differ (all p > 0.10, Table 2).
In this cross-sectional study of 72 older subjects, we found that AMTS and its derivative versions had good (c-statistic from 0.83 to 0.87) concordance with MMSE after correction according to Mungas et al.  in determining a suspicion of cognitive impairment. This does not significantly differ across various English language versions of AMTS currently in use, and the Polish modification of the test. This is reflected by a significant correlation between scores obtained from different versions of AMTS.
AMTS is an easy to perform tool for screening assessment of cognition in older subjects.Many modifications of the test exist, however whether their screening value is comparable has never been tested.We found that irrespective of modifications of questions in AMTS, its screening performance is satisfactory.We advocate use of AMTS and its variants in the quick cognitive screening of older patients.