Westborough Youth and Family Services is offering free, anonymous mental health screenings Thursday from 10 a.m. to 7 p.m. in its offices at 45 West Main St. The annual event, being held in association with the Assabet Valley Pastoral Counseling Center as part of National Depression Screening Day, is open to r esidents age 6 and up. The screenings will check for signs of depression, anxiety, bipolar disorder, and post-traumatic stress disorder, and involve a questionnaire and a meeting with a counselor in a process that will take approximately 30 minutes. Those interested are encouraged to set up an appointment by calling 508-366-3090. An anonymous online screening test is also available at www.mentalhealthscreening.org.