Big traits study results

This is a simplified account of what I call my "Big Traits Study" which suggests 105 traits that are distinct to PDA but not gneral autism.

Method

In 2016, I invited fellow members of an online adult PDA group to suggest potential, distinct PDA traits for inclusion in an in-group poll. The 228 traits were suggested were put into a Google Form poll, without editing any of the wordings. Members of the same adult PDA group were then invited to rank each of the 228 with 0 equalling "not at all" and 5 equalling "majorly". The results were filtered to select:

    All traits scoring an average of 3.5+ out of 5 

    A small number of very unusual traits (such as making up new names for people)

    Traits that were considered to be PDA indicators (being late learning to talk and being dyspraxic)

155 of the original 228 traits made it through the filter and were transferred to a second Google Form, which was completed by 290 people identify as PDA and 90 people who identified as being autistic but not PDA.

Results

In 2019, a Nottingham University Forensic Psychology PhD student, Grace Trundle, carried out a T-test analysis on the data, and found that, of 155 traits, 105 (over two thirds) showed a significant difference between PDA and “general” autism.

The results of Trundle's T test analysis are included below. For simplicity, Grace termed people who identified as autistic but not PDA as "ASD not PDA". 

According to Grace Trundle's analysis, PDA scored higher in every instance.

Variable	Group Means^	Is the difference between groups statistically significant*?
I often find that I cannot motivate myself to carry out even simple tasks.	ASD Non-PDA 3.5000 PDA 4.3034	Yes
I avoid even potentially pleasurable and advantageous activities because of innate anxiety and demands.	ASD Non-PDA 3.3000 PDA 4.1862	Yes
My demand avoidance varies in intensity.	ASD Non-PDA 3.17 PDA 4.20	Yes
When demand avoidance kicks in, there is nothing in the world that will deactivate it.	ASD Non-PDA 2.86 PDA 4.21	Yes
Motivation is like an elusive shadow; I can never quite reach it	ASD Non-PDA 3.14 PDA 3.86	Yes
If someone tells me to do something, I feel an overwhelming aversion to doing it.	ASD Non-PDA 2.79 PDA 4.28	Yes
Sometimes demand avoidance and anxiety cause me to have physical symptoms.	ASD Non-PDA 2.96 PDA 4.14	Yes
I need to be free from constraints, including being with other people.	ASD Non-PDA 3.48 PDA 4.02	Yes
I hate direct compliments  they may lead to avoidance e.g.: 'you're brilliant at maths!' ... I don't try at maths again.	ASD Non-PDA 2.38 PDA 3.35	Yes
I put off going to the grocery.	ASD Non-PDA 3.37 PDA 3.85	Yes
I may arrive places late, as I avoid until the last minute.	ASD Non-PDA 2.42 PDA 3.73	Yes
I don’t pay bills on time even when I have the money.	ASD Non-PDA 2.18 PDA 3.20	Yes
I put off doing laundry unless there's something that I want to wear, and it needs washing.	ASD Non-PDA 2.83 PDA 3.64	Yes
I find it hard to motivate myself to bathe.	ASD Non-PDA 2.82 PDA 3.63	Yes
I find it hard to switch thoughts off.	ASD Non-PDA 4.06 PDA 4.62	Yes
I have had/have panic attacks.	ASD Non-PDA 3.50 PDA 3.92	Yes
I have self-medicated to reduce anxiety.	ASD Non-PDA 2.69 PDA 3.18	Yes
I am self-conscious.	ASD Non-PDA 3.98 PDA 4.31	Yes
I feel anxiety over making social mistakes.	ASD Non-PDA 4.10 PDA 4.36	Yes
I panic if I feel I've been seen getting something wrong.	ASD Non-PDA 3.92 PDA 4.38	Yes
I don't want anyone watching me doing things.	ASD Non-PDA 4.03 PDA 4.38	Yes
I want to get on with people, but I never know what to say.	ASD Non-PDA 3.72 PDA 3.88	No
I worry I will lose face in front of my social circle: worry that I might let my mask slip.	ASD Non-PDA 3.38 PDA 3.72	Yes
I copy tone of voice and accents, trying to 'fit in' to social circles.	ASD Non-PDA 2.90 PDA 3.56	Yes
I try to say the right things, with the right expressions and body language when I talk to people, but never know if I have got it right.	ASD Non-PDA 3.40 PDA 3.88	Yes
I have difficulty making friends.	ASD Non-PDA 4.04 PDA 3.88	No
It takes a long time for people to get to know me.	ASD Non-PDA 4.17 PDA 4.18	No
I am sociable, but lack depth in my understanding of people.	ASD Non-PDA 3.22 PDA 3.76	Yes
I find it hard to join in group activities, e.g. team sports.	ASD Non-PDA 4.24 PDA 4.24	No
I prefer a few close friends.	ASD Non-PDA 4.42 PDA 4.43	No
I am fussy about my partner.	ASD Non-PDA 3.77 PDA 4.08	Yes
I don’t respond to invitations.	ASD Non-PDA 3.22 PDA 3.63	Yes
Uninvited guests feel more like an intrusive burden and imposition, than a welcome surprise.	ASD Non-PDA 4.39 PDA 4.14	Yes
I have developed aversions towards people.	ASD Non-PDA 3.76 PDA 4.11	Yes
I am not comfortable with people touching me or coming too close.	ASD Non-PDA 3.78 PDA 3.95	No
I miss social cues.	ASD Non-PDA 3.89 PDA 3.98	No
I am a very loyal friend.	ASD Non-PDA 4.26 PDA 4.04	No
I enjoy social activities, but I also find them confusing and exhausting.	ASD Non-PDA 3.82 PDA 4.06	No
I find making eye contact uncomfortable in some situations.	ASD Non-PDA 4.03 PDA 3.91	No
I don’t respond to social status or age in the way I interact with people.	ASD Non-PDA 3.77 PDA 4.23	Yes
Respect and trust are important to me.	ASD Non-PDA 4.67 PDA 4.38	Yes
I develop very strong, passionate interests.	ASD Non-PDA 4.37 PDA 4.41	No
I have had/have obsessions about people.	ASD Non-PDA 3.48 PDA 4.09	Yes
I develop attachments to particular places.	ASD Non-PDA 3.56 PDA 4.02	Yes
I have hyper-focus and can work for hours on an interest without taking breaks.	ASD Non-PDA 4.16 PDA 4.11	No
My freezing and shutting down are frequently misinterpreted.	ASD Non-PDA 3.71 PDA 4.22	Yes
Freezing feels like a safe response.	ASD Non-PDA 3.17 PDA 3.81	Yes
I have had/have Jekyll and Hyde behaviour.	ASD Non-PDA 3.02 PDA 4.31	Yes
I am frequently overloaded.	ASD Non-PDA 4.07 PDA 4.43	Yes
I was late in learning to talk.	ASD Non-PDA 1.98 PDA 2.38	Yes
I was  a good reader from early age.	ASD Non-PDA 3.98 PDA 3.66	No
I was independent from an early age, wanted to do everything myself.	ASD Non-PDA 3.73 PDA 3.60	No
I understood fairness from an early age.	ASD Non-PDA 3.52 PDA 3.16	Yes
I felt like an outcast at school.	ASD Non-PDA 4.46 PDA 4.37	No
I used to daydream a lot as a child.	ASD Non-PDA 4.13 PDA 4.15	No
I had a rich fantasy world, which I preferred to reality.	ASD Non-PDA 3.60 PDA 3.97	Yes
As a child, I interacted more easily with adults.	ASD Non-PDA 4.06 PDA 4.25	No
As a child, I had difficulty getting along with children of a similar age.	ASD Non-PDA 4.10 PDA 4.19	No
I have good reading comprehension skills.	ASD Non-PDA 4.19 PDA 3.90	No
My academic attainment has not been a true indication of my intellectual ability.	ASD Non-PDA 3.70 PDA 4.27	Yes
I find it impossible to sit quietly in class as I fidget and ask questions/argue points the teacher/tutor makes.	ASD Non-PDA 2.88 PDA 3.78	Yes
I need to understand the author’s intent or meaning. I can't gloss over things. I will re-read to be sure I got it.	ASD Non-PDA 3.67 PDA 3.89	No
I am good with words	ASD Non-PDA 3.83 PDA 3.90	No
I love analogy and metaphor and hyperbole.	ASD Non-PDA 3.21 PDA 3.45	No
I like word games.	ASD Non-PDA 3.32 PDA 3.30	No
I like making puns.	ASD Non-PDA 3.17 PDA 3.19	No
I like making up rhymes.	ASD Non-PDA 2.71 PDA 3.02	No
I make up new words to replace common words.	ASD Non-PDA 2.39 PDA 3.10	Yes
I mispronounce words deliberately.	ASD Non-PDA 2.11 PDA 2.61	Yes
I make up new names for people.	ASD Non-PDA 2.18 PDA 2.94	Yes
I make odd noises.	ASD Non-PDA 2.80 PDA 3.45	Yes
My verbal ability may disguise my lack of processing speed.	ASD Non-PDA 3.38 PDA 3.93	Yes
I hate talking on the phone.	ASD Non-PDA 4.26 PDA 3.75	Yes
I have had/have depression.	ASD Non-PDA 3.90 PDA 3.99	No
I have had/have sleep problems.	ASD Non-PDA 3.62 PDA 4.39	Yes
I have dyspraxia (clumsiness).	ASD Non-PDA 2.74 PDA 2.96	No
I have irregular eating habits.	ASD Non-PDA 3.16 PDA 3.87	Yes
I have hypersensitivity of any/all senses.	ASD Non-PDA 3.86 PDA 4.10	No
I react differently to pain than other people seem to do.	ASD Non-PDA 3.43 PDA 3.91	Yes
When unsupported, my anxiety, hyper-emotionality and social alienation has escalated to mirror recurrent depressive disorder or borderline, narcissistic or dissocial personality disorder.	ASD Non-PDA 2.72 PDA 3.75	Yes
I have had/have over the top seeming emotional reactions.	ASD Non-PDA 4.09 PDA 4.53	Yes
I have had/have mood swings.	ASD Non-PDA 3.82 PDA 4.58	Yes
I am prone to hyper behaviour/silliness.	ASD Non-PDA 3.17 PDA 4.05	Yes
I have a fantastic sense of humour.	ASD Non-PDA 3.28 PDA 3.81	Yes
I enjoy role play, comedy and accents.	ASD Non-PDA 2.78 PDA 3.62	Yes
I have difficulty performing like an adult, in pretty-much all facets of life.	ASD Non-PDA 3.22 PDA 3.58	Yes
I like to communicate.	ASD Non-PDA 2.93 PDA 3.41	Yes
I hate being ignored.	ASD Non-PDA 3.32 PDA 4.34	Yes
People misunderstand my friendly sarcasm and are sometimes upset.	ASD Non-PDA 3.19 PDA 3.71	Yes
I can be oversensitive e.g. ' he looked at me in a funny way'.	ASD Non-PDA 3.50 PDA 4.26	Yes
I have trouble with family relations, e.g., my mother.	ASD Non-PDA 3.44 PDA 3.92	Yes
I hate injustice.	ASD Non-PDA 4.42 PDA 4.54	No
I like to help people.	ASD Non-PDA 4.09 PDA 4.09	No
I am empathic (feel empathy).	ASD Non-PDA 3.74 PDA 3.80	No
I can give the impression of having no empathy.	ASD Non-PDA 3.59 PDA 3.90	Yes
I am bad at budgeting.	ASD Non-PDA 3.06 PDA 3.79	Yes
Don't rush me!	ASD Non-PDA 4.16 PDA 4.69	Yes
I am impulsive.	ASD Non-PDA 2.84 PDA 4.04	Yes
I feel a need to be in control.	ASD Non-PDA 3.89 PDA 4.64	Yes
I need constant choice in any situation to feel in control.	ASD Non-PDA 3.17 PDA 4.30	Yes
I don’t handle criticism well.	ASD Non-PDA 3.77 PDA 4.43	Yes
I can't cope with being told what to do.	ASD Non-PDA 3.06 PDA 4.42	Yes
I can't cope with being kept waiting.	ASD Non-PDA criticism PDA 4.22	Yes
I expect others to stick to rules.	ASD Non-PDA 4.16 PDA 4.41	Yes
I am critical of others.	ASD Non-PDA 3.53 PDA 4.08	Yes
I have found that learning to suspend judgment and let it go is helpful.	ASD Non-PDA 3.43 PDA 3.13	Yes
I always want to be right.	ASD Non-PDA 3.51 PDA 4.23	Yes
I think for myself.	ASD Non-PDA 4.06 PDA 4.09	No
I am open minded: more liberal, more willing to hear all sides, less judgemental.	ASD Non-PDA 3.84 PDA 3.24	Yes
My sense of fairness may not apply to what I expect from others.	ASD Non-PDA 3.19 PDA 3.85	Yes
I am bad at making complex decisions.	ASD Non-PDA 3.71 PDA 4.00	No
I am intelligent.	ASD Non-PDA 4.09 PDA 4.30	No
My IQ score is high.	ASD Non-PDA 3.71 PDA 3.85	No
My intelligence has gotten in the way of professionals spotting my problems.	ASD Non-PDA 3.66 PDA 4.16	Yes
I get confused as to why people treat me as if I’m stupid.	ASD Non-PDA 3.31 PDA 3.61	No
I get confused as to why people tell me I am manipulative.	ASD Non-PDA 2.46 PDA 3.58	Yes
I can be charming.	ASD Non-PDA 2.90 PDA 4.20	Yes
I like trying to get to the bottom of how things work, especially people/social things.	ASD Non-PDA 3.63 PDA 3.98	Yes
I have an interest in psychology.	ASD Non-PDA 3.79 PDA 3.70	No
I have an interest in philosophy & ethics.	ASD Non-PDA 3.29 PDA 3.40	No
I have my own set of ethics that do not necessarily correspond to society's, the law, etc.	ASD Non-PDA 3.34 PDA 3.89	Yes
I take promises literally (both self-made and made by others).	ASD Non-PDA 4.17 PDA 4.22	No
I think literally.	ASD Non-PDA 3.84 PDA 4.05	No
I am logical rather than emotional: I analyse myself, other people and social situations.	ASD Non-PDA 3.92 PDA 3.46	Yes
I have black and white thinking, everything is either great or awful, no in between.	ASD Non-PDA 3.11 PDA 3.79	Yes
I love animals.	ASD Non-PDA 4.17 PDA 4.16	No
I may leap to the rescue of a person or animal being abused.	ASD Non-PDA 3.73 PDA 4.10	Yes
I have a strong Be Perfect drive.	ASD Non-PDA 3.61 PDA 3.79	No
I want to please people.	ASD Non-PDA 3.77 PDA 3.87	No
I am imaginative/creative.	ASD Non-PDA 3.57 PDA 4.08	Yes
I experience vivid dreams.	ASD Non-PDA 3.47 PDA 4.03	Yes
have been enthusiastic for starting a project - but never completed it ... e.g. craft.	ASD Non-PDA 3.89 PDA 4.32	Yes
I can come up with unconventional solutions that surprise people.	ASD Non-PDA 3.70 PDA 3.99	Yes
I may put myself in potentially hazardous situations and be taken advantage of.  I am very vulnerable because of this.	ASD Non-PDA 3.16 PDA 3.87	Yes
I cancel plans at the last minute.	ASD Non-PDA 2.81 PDA 3.77	Yes
I need down time alone to rest in order to counteract stress.	ASD Non-PDA 4.64 PDA 4.71	No
I like being at home, spending time alone with the comfort of familiarity.	ASD Non-PDA 4.72 PDA 4.64	No
I find comfort in some routines, but don’t like them imposed on me.	ASD Non-PDA 4.09 PDA 4.56	Yes
I like to hear the same songs/watch the same TV show/read the same book series.	ASD Non-PDA 3.87 PDA 4.23	Yes
I get lost in books.	ASD Non-PDA 3.74 PDA 3.38	No
I find it hard to pay attention to other people, TV shows, etc.	ASD Non-PDA 3.20 PDA 3.50	Yes
I struggle with transitions, even subtle ones.	ASD Non-PDA 3.36 PDA 3.95	Yes
I have an increasing sense of foreboding as appointments approach.	ASD Non-PDA 3.80 PDA 4.33	Yes
I hate housework but am embarrassed of having a messy home.	ASD Non-PDA 3.62 PDA 3.90	No
I don’t like to lose or be last.	ASD Non-PDA 3.33 PDA 4.03	Yes
I am self-aware.	ASD Non-PDA 3.83 PDA 3.91	No
I have a fascination with people who are self-aware.	ASD Non-PDA 2.92 PDA 3.31	Yes
I can’t cope with being told what to do by bosses and managers.	ASD Non-PDA 2.61 PDA 3.88	Yes
I am not motivated by money, but will work for hours unpaid, so long as there is no demand that I do this.	ASD Non-PDA 3.00 PDA 3.46	Yes
My perfectionism in work causes anxiety and makes it hard for me to keep up.	ASD Non-PDA 3.57 PDA 3.74	No
I have a hard time following through with multistep processes.	ASD Non-PDA 3.65 PDA 3.92	No
I can’t cope with deadlines.	ASD Non-PDA 3.07 PDA 4.06	Yes
I can’t cope with being confined to a workplace.	ASD Non-PDA 2.74 PDA 3.85	Yes
I can't cope with being an employee unless given a lot of authority and/or autonomy.	ASD Non-PDA 2.80 PDA 3.85	Yes
I can’t cope with tax returns.	ASD Non-PDA 3.01 PDA 3.72	Yes

Independent Samples t-test. IV=Group Membership (Non-PDA ASD vs PDA). DV=Variables listed. Statistics for unequal variances examined when Levene’s Test for Unequal Variances p<0.05.
*p<0.05
^Difference between groups not calculated using group means only. Mean scores documented for descriptive purposes.