ALERT! Warning: your browser isn't supported. Please install a modern one, like Firefox, Opera, Safari, Chrome or the latest Internet Explorer. Thank you!
Log inLog in to ACORN Wiki. | RegisterSign on to ACORN Wiki.

You are here: ACE » ACEOutcomesEvaluationMethod

ACE Treatment Outcomes Evaluation Method

ACE reports of aggregated outcomes include information on the magnitude of change (reported as effect size) and the distribution of change, reported as percentage of patients significantly improved, somewhat improved, unchanged, or somewhat worse, or significantly worse.


Severity adjust effect sizes, which control for differences in case mix, are used when reporting clinicians and/or practices. For purposes of ACE reports, effect size is calculated using the standard deviation at intake for all patients with scores in the clinical range at intake. Clinicians or organizations with effect sizes between 0.5 and 0.8 are described as effective while those with effect sizes greater than 0.8 are described as highly effective.

Patients are classified as somewhat improved (or worse) if the pre-post change exceeds the standard error of measurement for the outcome measure. If change exceeds the Reliable Change Index the patient is classified significant improved (or worse).

ACORN adult questionnaires have an average reliability of 0.91 (depending on the number and mix of items). Assuming a reliability of 0.91, the Standard Error of Measurement is 0.3 effect size, while the Reliable Change Index is 0.83 effect size.

For purposes of reporting, the following cut scores are used to classify change:
  • Significantly improved: effect size >0.8
  • Somewhat improved: effect size >0.3
  • No change: effective between -0.3 and 0.3
  • Somewhat worse: effect size < -0.3
  • Significant worse: effect size <-0.8

Sample ACE Reports Graphs

  • ACEChangeCriteria.xls: This is the Excel file used to calculated the SEM and RCI for the ACORN measures

This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding ACORN Wiki? Send feedback
Syndicate this site RSS