# Conversion between the Rowland Universal Dementia Assessment Scale and Mini‐Mental State Examination test scores in majority and minority populations

## TL;DR

This study creates a conversion table to compare two cognitive screening tools, RUDAS and MMSE, improving their use in diverse populations.

## Contribution

A reliable conversion table between RUDAS and MMSE scores is developed and validated in majority and minority populations.

## Key findings

- A conversion table was developed using the equipercentile equating method.
- The conversion table showed excellent reliability with intraclass correlation coefficients of 0.92 in both validation samples.
- The table was validated in Spanish-speaking participants from majority and minority populations.

## Abstract

Despite the Rowland Universal Dementia Assessment Scale (RUDAS) having significant advantages as a cognitive screening tool, particularly for minority populations, the Mini‐Mental State Examination (MMSE) test is the most widely used test for cognitive screening in Alzheimer's disease (AD). This study aimed to develop a conversion table to predict MMSE scores from observed RUDAS scores, allowing an easy‐to‐use method to compare both screening tests.

The equipercentile equating method was used to develop the conversion table using a training sample consisting of cognitively intact participants and individuals with early‐stage AD. The resulting conversion table was validated in two samples, comprising participants from majority and minority populations assessed in Spanish.

The conversion table demonstrated excellent reliability with intraclass correlation coefficients of.92 in both validation samples.

This study provides a conversion table between RUDAS and MMSE scores, improving the comparability of these cognitive screening tools for use in clinical and research purposes.

This study aimed to develop a conversion table to predict MMSE scores from observed RUDAS scores, allowing an easy‐to‐use method to compare both screening tests. The equipercentile equating method was used to develop the conversion table using a training sample consisting of cognitively intact participants and individuals with early‐stage AD. The resulting conversion table was validated in two samples, comprising participants from majority and minority populations assessed in Spanish, showing excellent reliability.