Validation of the French Version of the Lithium Knowledge Test (LKT) (LKT)

Validation of the French Version of the Lithium Knowledge Test (LKT) for Patients Treated With Lithium in Psychiatric Unit Hospitals

Lithium is a drug used to treat several psychiatric illnesses. This medication requires particular vigilance because it has a narrow therapeutic margin: the dose necessary to obtain an effective treatment is close to the toxic dose.

The blood dosage of the drug and the patient's knowledge of the drug are necessary to optimize and secure the drug intake.

The objective of this observational study is to confirm that the score obtained by the LKT lithium knowledge self-questionnaire translated into French is representative of the knowledge of patients treated with lithium.

Participants will be asked to complete this questionnaire twice, and the scores obtained will be compared to the blood lithium level to see if a good score is associated with an effective blood lithium concentration.

Study Overview

• Status: Terminated
• Conditions: Patient Treated With Lithium, With Bipolar or Schizo-affective Disorder, Hospitalized in a Psychiatric Ward

• Study Type: Observational
• Enrollment (Actual): 22

Contacts and Locations

Study Locations

• France
  • Lille, France
    • CHU de Lille

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients hospitalized in an adult psychiatric ward or staying in an EPSM in the cities included in this study

Description

Inclusion Criteria:

• Patient hospitalized in a psychiatric ward or in an EPSM for more than 10 consecutive days
• Patient treated with IR or ER lithium LI
• Patient over 18 years of
• Patient on a fixed dosage of lithium for more than 5 days prior to blood sampling for lithiaemia testing
• Obtain patient's non-opposition

Exclusion Criteria:

• Clinically unstable patient or patient with a cognitive disorder that makes it impossible to perform interview and/or completion of the LKT self-questionnaire
• Patients under guardianship or trusteeship
• Illiterate patients
• Patient with a therapeutic target concentration different from general recommendations (e.g. elderly subject)
• Patient receiving a pharmaceutical interview or any other interview between the completion of the 1 and 2nd questionnaires, likely to modify the LKT score.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of the factorial validity of the score from the first completed LKT self-questionnaire	Baseline: percentage of inertia explained by the first component of the principal component analysis Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 yaers

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of the internal consistency of the LKT score: is acceptable if Cronbach's alpha is greater than 0.7	Baseline after data collection: percentage of inertia explained by the first component of the principal component analysis Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 yaers
External validity of the LKT self-questionnaire by measuring the correlation between the lithiaemia assay at D0 and the score obtained on the self-questionnaire at D0.	Baseline after data collection: percentage of inertia explained by the first component of the principal component analysis Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 yaers
Evaluation of the test/retest reliability of the LKT self-questionnaire score measured at D0 and D4.	Baseline and 4 days after data collection Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 years
Comparison of lithiaemia at D0 between patients with good knowledge (i.e. a LKT self-questionnaire score at D0 > 6) and those with poor knowledge of treatment	Baseline and 4 days after data collection Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 years
Search for factors associated with the LKT self-questionnaire score at J0.	Baseline and 4 days after data collection Maximum time to obtain scores for 300 self-questionnaires: 2 years	2 years

Collaborators and Investigators

• Sponsor: University Hospital, Lille

Study record dates

Study Major Dates

• Study Start (Actual): November 28, 2023
• Primary Completion (Actual): November 28, 2025
• Study Completion (Actual): November 28, 2025

Study Registration Dates

• First Submitted: September 5, 2023
• First Submitted That Met QC Criteria: September 11, 2023
• First Posted (Actual): September 13, 2023

Study Record Updates

• Last Update Posted (Actual): May 22, 2026
• Last Update Submitted That Met QC Criteria: May 19, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Lithium; security; observance; Lithium Knowledge Test
• Additional Relevant MeSH Terms: Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Psychotic Disorders
• Other Study ID Numbers: 2020_98

Drug and device information, study documents

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