Table 3.
Basic symptoms checklist item pool, with corresponding Schizophrenia Proneness Instrument Adult Version item numbers.
| Schizophrenia Proneness Instrument Adult Version item number | Basic symptom checklist item wording |
| A1.1 | Doing new things has been more stressful than usual |
| A1.2 | Crowds or people have been more stressful than usual |
| A1.3 | Doing things in a hurry has been more stressful than usual |
| A2.2 | I have felt empty and flat |
| A3 | I seemed to care less about people than I usually do |
| B1 | I have found it very hard to do two things at once |
| B2 | I have found myself more easily distracted than usual |
| B3 | My concentration has been worse than usual |
| B4 | I have been forgetting things I’ve done less than an hour before |
| B5 | My thoughts have been slower than usual |
| B6 | I haven’t had the energy for thinking |
| C1 | Even simple choices have been difficult |
| C2 | Random thoughts have popped into my head |
| C3 | My mind has sometimes gone blank |
| C4 | It’s been hard to follow what people say |
| C5 | I have found it hard to say what I mean |
| C6 | I forgot things I was told almost immediately |
| D1 | It’s been hard to decide what I’m feeling |
| D2 | I have felt more emotional about everyday things |
| D3 | My head’s been buzzing with lots of thoughts |
| D4 | Random things seemed to have a personal meaning for a moment |
| D5 | People have looked somehow different than usual |
| E1-E5 | I’ve had some unusual feelings in my body |
| E6 | It sometimes felt like part of my body had swollen up or shrunk |
| F1 | Light has seemed very bright |
| F2 | I have sometimes seen flashes of light |
| F3 | Things have looked the wrong size |
| F4 | I have noticed sounds more than usual |
| F5 | Sounds have seemed different than usual |
| F6 | My body has sometimes felt like it didn’t belong to me |
| O1a | Sometimes thoughts and images that are unimportant and have no special meaning keep repeating over and over in my mind and I can’t push them away |
| O2.1 | Sometimes I have mixed up real and imaginary things |
| O2.2 | Sometimes I have mixed up real and imaginary memories |
| O3a | Sometimes I take things literally when they are not meant that way. For example, I sometimes misunderstand sayings or metaphors |
| O4.1 | Things seemed closer or further away than they actually were |
| O4.2 | Things have seemed to change shape |
| O4.3 | Colors have seemed different than usual |
| O4.4 | Sometimes when I looked in the mirror I looked different |
| O4.5 | Things that I saw sometimes seemed to move |
| O4.6b | Things have looked wonky or like there was more than one |
| O4.7 | Judging distance or size has been hard |
| O4.8 | Lines have looked somehow wrong |
| O4.9 | If I stared at something and then looked away I could still see it afterwards |
| O4.10 | I have had “tunnel vision” |
| O5.1 | I could sometimes hear sounds that didn’t seem quite real |
| O5.2a | Sometimes I hear sounds which I heard a few minutes ago or even hours before |
| O5.2 | Sounds have sometimes seemed to continue after I know they have stopped |
| O6.1 | Things have smelt different from usual |
| O6.2 | Things have tasted different from usual |
| O6.3 | Objects have felt different from usual |
| O7 | At times I could not take my eyes off something |
| O8 | Everything around me has seemed somehow not real |
| O9.1a | Sometimes I make certain movements even though I had no intention to, like I have lost control of my body |
| O9.2a | I have sometimes spoken without meaning to |
| O10 | My body has sometimes got “stuck” for a short time |
| O11 | I have had to think about things that I usually do automatically |
aWording updated in response to piloting in nonclinical sample.
bWording updated in response to feedback from beta tester in this study. Original wording: Things have looked crooked or like there was more than one.