Five Digits Test - Validation of a Neuropsychological Test of Inhibition for Patients With Neuropsychiatric Conditions

Neuropsychiatric conditions such as Attention Deficit Hyperactivity Disorder (ADHD) and autism are characterized by specific deficits in cognitive functions. Thus, neuropsychological assessment is a critical part of the diagnostic process for these conditions. Inhibition is a specific function of interest during these examinations, since it is often affected in patients with ADHD and/or autism. The Five Digits Test (FDT) is a newly developed test measuring inhibition, without requirements of reading ability, and only limited requirements of language proficiency.

The aim of this study is to investigate the validity of the FDT in patients with neuropsychiatric conditions. The FDT will be validated using the following research questions:

1. Is the FDT equivalent to the standard neuropsychological test of inhibition, the Color-Word Interference Test from the Delis-Kaplan Executive Function System in patients with neuropsychiatric conditions? (Convergent validity)
2. Is the FDT consistent with self-assessment of inhibition and behavioral regulation in every day life using the Behavior Rating Inventory of Executive Function - Adult Version (BRIEF-A)? (Ecological validity)
3. Are there differences in validity in the first two research questions due to language background or due to reading and writing difficulties?
4. Are there differences between patients with neuropsychiatric conditions and healthy controls in the performance of the FDT?

Study Overview

• Status: Recruiting
• Conditions: ADHD; Autism
• Intervention / Treatment: Diagnostic test: Five Digits Test

Detailed Description

In a cross-sectional design, patients with or under examination for either ADHD or autism will be invited to participate in the project. Patients will receive both written and oral information about the project and sign informed consent before data collection begins. After this, patients will complete the BRIEF-A and answer some questions regarding demographic and health related factors. Before starting the testing session patients will be randomly assigned to perform FDT first or the CWIT first, to control for test-retest or learning effects. Healthy controls will be recruited through advertisements, otherwise the data collection procedure will be the same as for patients.

The validity of FDT will be validated against the CWIT and the BRIEF-A using Pearson and/or Spearman correlation coefficients. The strength of the correlations will be interpreted using Cohen's (1992) cutoffs of weak (0.1), medium (0.3) and strong (0.5) correlations. Additionally, multiple linear regressions will be performed to investigate and adjust for background variables. Student's t-tests and/or ANCOVAS will be used to compare differences between groups.

• Study Type: Observational
• Enrollment (Estimated): 150

Contacts and Locations

• Study Contact: Name: Nils Berginström, PhD; Phone Number: +46907868864; Email: nils.berginstrom@umu.se

Study Locations

• Sweden
  • Umeå, Sweden, 90637
    • Recruiting
    • Umeå University, Umeå University Hospital
    • Contact: Nils Berginström; Phone Number: 0730300303; Email: nils.berginstrom@umu.se

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

All patients referred to neuropsychiatric examination, ADHD and/or autism at the Psychiatric Clinic at Umeå University Hospital will be offered to participate in the study. A comparison group of healthy volunteers will be recruited using advertising.

Description

Inclusion Criteria:

• age 18 and above
• Diagnosed with a ADHD or Autism, alternatively under examination these diagnoses

Exclusion Criteria:

• Addiction of alcohol or other substances
• Not speaker of Swedish to such extent that cannot read or comprehend the informed consent forms
• On sedatives, such as sleep or pain medication
• Not being able to participate in a neuropsychological examination, or to give informed consent

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy Controls	Diagnostic test: Five Digits Test; Neuropsychological test of Inhibition
ADHD; Patients with Attention Deficit Hyperactivity Disorder (ADHD)	Diagnostic test: Five Digits Test; Neuropsychological test of Inhibition
Autism; Patients with Autism	Diagnostic test: Five Digits Test; Neuropsychological test of Inhibition

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Convergent validity of the Five Digits Test	The results of the Five Digits Test will be validated against the test Color-Word Interference Test from Delis-Kaplan Executive Functions system. The validation will be performed by calculation of the correlation coefficient (Pearson or Spearman) between these tests. Time to completion will be used as outcome in both tests, where slower times indicate lower performance.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ecological validity of the Five Digits Test	The results of the Five Digits Test will be validated against self-assessment questionnaire BRIEF - Behavior Rating Inventory of Executive Function. Time to completion in each condition is the outcome of the Five Digits Test, where a slower performance indicate a lower score. Raw scores (where higher score indicate a larger degree of problems) and scaled scores (where lower score indicate a larger degree of problems) for specific scales/indexes (Inhibition; Emotional Control; Self-monitoring; Behavioral Regulation Index) are the outcomes of interest from the BRIEF. The validation will be performed by calculation of the correlation coefficient (Pearson or Spearman) between performance on the FDT and the scales of the BRIEF.	Baseline

Collaborators and Investigators

• Sponsor: Umeå University
• Collaborators: Region Västerbotten

Study record dates

Study Major Dates

• Study Start (Actual): January 21, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: March 31, 2026
• First Submitted That Met QC Criteria: April 13, 2026
• First Posted (Actual): April 15, 2026

Study Record Updates

• Last Update Posted (Actual): April 15, 2026
• Last Update Submitted That Met QC Criteria: April 13, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: ADHD; Autism; Inhibition; Neuropsychological Assessment
• Additional Relevant MeSH Terms: Autism Spectrum Disorder; Mental Disorders; Neurodevelopmental Disorders; Child Development Disorders, Pervasive; Attention Deficit and Disruptive Behavior Disorders; Behavior; Autistic Disorder; Attention Deficit Disorder with Hyperactivity; Inhibition, Psychological
• Other Study ID Numbers: 2025-06699-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: National regulations about sharing data regarding patients.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No