Note 8 - Employee Benefit Plan	12 Months Ended
Dec. 31, 2022
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	8. Employee Benefit Plan The Psychemedics Corporation 401(k) Savings and Retirement Plan (the “401(k) Plan”) is a qualified defined contribution plan in accordance with Section 401(k) of the Internal Revenue Code. All employees over the age of 21 are eligible to make pre-tax contributions up to a specified percentage of their compensation. Under the 401(k) Plan, the Company may, but is not obligated to, match a portion of the employees’ contributions up to a defined maximum. Matching contributions of zero, zero, and $198 thousand were made in the years ended December 31, 2022, 2021 and 2020, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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