California Code, Business and Professions Code - BPC § 2425

(a) The board may prepare and provide electronically or by mail to every licensed physician at the time of license renewal a questionnaire containing any questions as are necessary to establish that the physician currently has no disorder that would impair the physician's ability to practice medicine safely.

(b) Each licensed physician shall complete, sign, and return the questionnaire either electronically or by mail to the board as a condition of renewing their license.

(c) The questionnaire described in this section shall not require disclosure of any information prohibited under Section 2090.