SOA Norms Report

  1. Introduction
  2. Collecting the Raw Data
    1. ARIC
    2. GMBI
    3. NACC
    4. MCSA
  3. Summarizing the Raw Data
    1. Demographics
    2. Instruments
  4. Generating the Normative Samples
    1. ARIC
    2. GMBI
    3. NACC
    4. MCSA
    5. Pooled
  5. Summarizing the Normative Data
    1. Demographics
    2. Instruments
    3. Groups by Instruments in the Pooled Sample
  6. Generating Instrument Level Models
    1. Notes on the Trail Making Tests
    2. A Note on the LDST
  7. Generating Domain Level Models
  8. Generating Algorithmic Classifications

Generating Instrument Level Models

Notes on the Trail Making Tests

Apart from the Trail Making Tests, every instrument in the SOA Battery is such that "a higher score on the test represents a better result." In order to address this issue, the values we use in the construction of our instrument level trails tests are "transformed" versions of the observed scores: \[ \text{Model} \text{ Trails} \text{ Value} = -1 \times \ln(\text{Observed} \text{ Trails} \text{ Score} )\]

Also, we had to deal with the fact that certain participants in our normative samples had "censored" trails times which could lead to multi-modal distributions of Model Trail Values. To address this issue, we set these censored trail times to missing in our normative samples.