Clinical Interview Questions to Assess for Schizotypal Personality Disorder

Note on interviewing: Taking a history may be difficult - patients often communicate in a distinctive, peculiar manner that needs interpretation. Allow pauses, tolerate vague answers, and gently probe further rather than supplying words.

DSM-5 Criterion 1 - Ideas of Reference (not delusions)

• "Have you ever noticed that things around you - things on TV, in newspapers, or things people say in public - seem to have a special message meant just for you?"
• "When you walk into a room and people are talking, do you sometimes feel they might be talking about you specifically, even if you're not sure?"
• "Have you had the sense that certain events or coincidences were somehow connected to you personally?"
• "Do numbers, colours, or patterns ever seem to carry a hidden meaning for you?"

DSM-5 Criterion 2 - Odd Beliefs and Magical Thinking

• "Do you believe in things like telepathy, clairvoyance, or being able to sense things before they happen?"
• "Have you ever felt that you could influence events or other people's thoughts just by thinking about them?"
• "Are you superstitious? Do you follow rituals or avoid certain things because you believe it will affect outcomes?"
• "Have you ever felt that you have a sixth sense or a special ability to perceive things others cannot?"
• "Do you believe in spirits, energies, or forces that interact with your life in a direct way?"

DSM-5 Criterion 3 - Unusual Perceptual Experiences

• "Have you ever had the sense that someone or something was nearby or in the room with you, even when you were alone?"
• "Have you ever noticed shapes, figures, or shadows out of the corner of your eye that turned out not to be there?"
• "Do you sometimes feel strange sensations in your body - like your limbs feel different, or you feel disconnected from yourself?"
• "Have you ever heard your name called, or faint sounds, when no one was there?"
• "Does your own face or body ever look strange or different to you when you look in the mirror?"

DSM-5 Criterion 4 - Odd Thinking and Speech

• "People sometimes tell me I'm hard to follow or that I go off on tangents - has anyone ever said something like that to you?"
• "Do you ever find it hard to put your thoughts into words in a way that others understand?"
• "Do people sometimes look confused when you're explaining something, even when it seems clear to you?"
• "Would you say you tend to think about things in a very detailed or symbolic way that others might find unusual?"

Observe: Is the patient's speech tangential, over-elaborate, or peppered with unusual words or metaphors? Does the patient use private language?

DSM-5 Criterion 5 - Suspiciousness / Paranoid Ideation

• "Do you generally trust people, or do you tend to be cautious because you feel others might have bad intentions toward you?"
• "Do you often feel that people are trying to take advantage of you, or are acting in ways that could harm you?"
• "When something goes wrong in your life, do you find yourself wondering if someone did something to cause it?"
• "Is it hard for you to confide in people because you worry they'll use what you've shared against you?"

DSM-5 Criterion 6 - Inappropriate or Constricted Affect

• "People who know you - would they say you're hard to read emotionally, or that your reactions don't always match the situation?"
• "Do you feel your emotions are muted, or that you don't feel things as strongly as others seem to?"
• "Have you been told you seem cold, detached, or not particularly warm with people?"

Observe: Does the patient smile at appropriate moments? Does their tone vary? Is there a flat or oddly cheerful quality when discussing distressing material?

DSM-5 Criterion 7 - Odd, Eccentric, or Peculiar Behavior or Appearance

• "Would people who know you describe your style - how you dress, how you present yourself - as unusual or different from most people?"
• "Do you have habits or routines that others might find strange or hard to understand?"
• "Have you ever been told that your mannerisms or the way you carry yourself is unusual?"

Observe: Unusual clothing choices, unkempt or idiosyncratic appearance, unusual mannerisms, self-referential gestures, mumbling to self.

DSM-5 Criterion 8 - Lack of Close Friends or Confidants

• "How many close friends would you say you have - people you can really talk to and trust?"
• "Have you ever had a close friendship that lasted a long time?"
• "Do you prefer to spend time alone, or is it more that you'd like connection but it just doesn't happen?"
• "How do you feel in social situations - parties, group gatherings, workplace events?"

DSM-5 Criterion 9 - Excessive Social Anxiety That Does Not Diminish with Familiarity

• "When you're around people, do you feel anxious even when you've known them for a while?"
• "Does being around people you know well feel any different from being around strangers, in terms of your anxiety level?"
• "When you feel anxious in social situations, what goes through your mind - are you worried about embarrassing yourself, or more that people might have bad intentions toward you?"
• "Even with family or long-term acquaintances, do you still find yourself on guard or wary?"

Supplementary Probes - Functioning and Longitudinal Course

• "Have you always been like this, or was there a time when things were different?"
• "Did people at school describe you as an odd or unusual child?"
• "How has this affected your work or career?"
• "Have you ever been in a romantic relationship? How did that go?"
• "Have you ever had times when these experiences became much stronger - where you felt you might be losing touch with reality?"

Red Flags Suggesting Schizotypal PD vs. Schizophrenia

Differential Considerations to Probe Specifically

• Schizoid PD: Schizotypal has magical thinking, perceptual distortions, and odd speech - schizoid does not. Ask about these directly.
• Paranoid PD: Both are suspicious, but schizotypal adds odd behavior, magical thinking, and perceptual distortions.
• Autism Spectrum: Schizotypal lacks the repetitive behaviors, early language delays, and restricted interests. Social anxiety in ASD is not paranoid in nature.
• BPD: BPD has emotional intensity, identity diffusion, and brief psychotic episodes under stress; schizotypal has a more stable eccentric baseline.

Ideas of Reference

• Do things on TV, in newspapers, or things people say in public ever seem to have a special message meant just for you?
• When you walk into a room and people are talking, do you feel they might be talking about you specifically?
• Have certain events or coincidences ever felt personally connected to you?

Magical Thinking & Odd Beliefs

• Do you believe in telepathy, clairvoyance, or sensing things before they happen?
• Have you ever felt you could influence events or others' thoughts just by thinking about them?
• Are you superstitious, or do you follow rituals to affect outcomes?
• Do you feel you have a sixth sense or special ability others don't have?

Unusual Perceptual Experiences

• Have you ever sensed someone or something was nearby when you were alone?
• Have you seen shapes or shadows out of the corner of your eye that weren't there?
• Does your own face or body ever look strange to you in the mirror?
• Have you ever heard your name called when no one was there?

Odd Thinking & Speech

• Have people told you that you're hard to follow or that you go off on tangents?
• Do people look confused when you explain something, even when it seems clear to you?
• Do you think about things in a symbolic or detailed way others find unusual?

Suspiciousness / Paranoid Ideation

• Do you tend to be cautious because you feel others might have bad intentions toward you?
• Do you often feel people are trying to take advantage of you?
• Is it hard to confide in people because you worry they'll use it against you?

Social Anxiety

• Do you feel anxious around people even after you've known them a long time?
• Does familiarity with someone reduce your anxiety, or do you stay on guard regardless?
• When anxious socially, are you worried about embarrassing yourself, or more that others have bad intentions?

Lack of Close Friends

• How many close friends do you have - people you can truly confide in?
• Have you ever had a long-lasting close friendship?
• Do you prefer being alone, or do you want connection but it just doesn't happen?

Odd Behavior & Appearance

• Would people describe how you dress or present yourself as unusual?
• Have you been told your habits or mannerisms are strange or hard to understand?

Affect

• Would others say you're hard to read emotionally, or that your reactions don't match the situation?
• Have you been told you seem cold or detached?

Longitudinal & Functional

• Have you always been this way, or was there a time when things were different?
• Did people at school describe you as odd or unusual?
• Have you ever been in a romantic relationship, and how did that go?
• Have you ever felt you might be losing touch with reality during stressful times?