1. Examine the Motives Behind the Behavior
Both autism and obsessive-compulsive disorder (OCD) entail recurring ritualistic behavior, such as rearranging items or repeating activities over and over again. People with autism feel comforted or fulfilled by these activities. People with OCD, on the other hand, feel compelled to engage in these activities because it reduces their stress or anxiety. The former is more pleasurable while the latter is a matter of psychological need.
2. Look for the Appearance of Savant Abilities
Some but not all people who suffer from autism exhibit savant behavior, which is marked by an extraordinary capacity with a specific subject or an uncanny memory. People with OCD don't develop savant abilities.
3. Check Social Compatibility
People with autism often have a difficult time interacting with the rest of society. Their symptoms may include lack of empathy towards others, repetitive use of language, tendency to say shocking or inappropriate things and difficulty in developing nonverbal social skills, such as facial expressions and the ability to make eye contact. While people with OCD may sometimes be shy or self-conscious, there is nothing about their condition that prevents them from interacting normally with other people. They can conduct conversations, exhibit a sense of social decorum and refrain from inappropriate comments or facial expressions.
4. See How Treatable the Symptoms Are
People with OCD tend to respond very well to treatment. Most of them benefit from psychological counseling, and many of them can reduce symptoms through medication, such as fluoxetine and clomipramine, which increases the levels of serotonin in their brains. People with autism, on the other hand, do not respond to such treatments. Their condition is more or less a set part of their personality and will remain with them through most of their lives. OCD symptoms can rise and fall throughout a person's life while someone with autism will always exhibit signs of the condition.
