Table 1
The Dutch Yips Study Questionnaire.
| 1. | What is your gender? | |||
| 2. | What is your year of birth? | |||
| 3. | What is your lowest golf-handicap thus far? | |||
| 4. | What is your present golf-handicap? | |||
| 5. | What is your dominant hand? | |||
| 6. | In what year did you started with playing golf?? | |||
| 7. | Do you have the yips? If no proceed to question 13 | |||
| 8. | When do you have the yips? During: Putting, Chipping, Irons and/or Driver | |||
| 9. | In what year were you struck by the yips? | |||
| 10. | In what hand do you have the yips? Right, Left, Both, Do not know | |||
| 11. | How many units of alcohol do you use in a week? 0, 1–7, 8–14, 14 + | |||
| 12. | How many cigarettes do you smoke in a week? 0, 1–10, 10 +, stopped | |||
| 13. | How fanatic are you in sports? 0–10 (0 = I do not care, 10 = most fanatic) | |||
| 14. | How fanatic are you in golf? 0–10 (0 = I do not care, 10 = most fanatic) | |||
| 15. | How tense are you before a golf match? 0–10 (0 = not at all, 10 = extreme) | |||
| 16. | Do you have obsessive thoughts or actions? | |||
| 17. | Do you use any kind of medication? If yes, please fill in | |||
| 18. | Are there any kind of neurological disorders in your family? | |||
| 19. | Do or did you have a neurological disorder? | |||
| 20. | Is there a first-degree family-member with the yips? | |||
| 21. | Dystonia Screening Questionnaire | Yes | No | Don’t know |
| 1. | Do you ever close both eyes spontaneously against your own will? | |||
| 2. | Do you frequently blink both eyelids against your own will? | |||
| 3. | Do you ever open and close your mouth spontaneously against your own will? | |||
| 4. | Do your lips ever move spontaneously against your own will? | |||
| 5. | Does your tongue ever move spontaneously against your own will? | |||
| 6. | Have you ever noticed alterations in voice lowering of voice, choked voice? | |||
| 7. | Does your head ever move spontaneously against your own will? | |||
| 8. | Do you ever shake your head against your own will? | |||
| 9. | Does your arm or hand ever move against your own will? | |||
| 10. | Does your arm or hand ever stop moving against your own will? |
Table 2
Results of the Dutch Yips Study.
| P-value | |||
| Participants (234) | Yips = 52 (22%) | Non-Yips = 182 (78%) | |
| Male gender | 45 (87%) | 105 (58%) | <0.001 |
| Age (mean, SD) | 61.7 (± SD 12.5) | 60.7 (± SD 12.0) | 0.6 |
| Dominant hand | |||
| Right | 45 (87%) | 157 (86%) | 0.91 |
| Left | 6 (12%) | 22 (12%) | 0.91 |
| Ambidextrous | 1 (2%) | 3 (2%) | NV |
| Years of Golf | 29.5 (+13.9) | 23.5 (+11.8) | 0.002 |
| Present HCP | 15.6 (+7.6) | 19.3 (+8.2) | 0.002 |
| Best HCP ever | 12.4 (+7.0) | 17.5 (+8.0) | < 0.001 |
| Smoking (ex) | 15 (29%) | 24 (13%) | 0.018 |
| Alcohol > 14 IU p/w | 9 (17%) | 16 (9%) | 0.14 |
| VAS | Mean (+SD) | Mean (+SD) | |
| VAS-Fanaticism in Golf | 7.4 (+1.3) | 7.0 (+1.6) | 0.1 |
| VAS-Fanaticism in Sports | 7.2 (+1.4) | 6.8 (+1.5) | 0.09 |
| VAS-Competition Tension | 6.0 (+2.1) | 5.6 (+2.0) | 0.2 |
| OCT | |||
| Yes | 5 (10%) | 11(6%) | 0.26 |
| No | 38 (73%) | 141(77%) | |
| ? | 9 (17%) | 30(16%) | |
| Medication | 21(40%) | 64(35%) | 0.3 |
| Beta-blocker | 5(9.6%) | 6(3%) | 0.07 |
| Medical neurological history | 5(9.6%) | 15(8%) | 0.47 |
| Family neurology | 8(15%) | 24(13%) | 0.42 |
| 1st degree Yips + | 10 (19%) | 8 (4%) | 0.0027 |
| 1st degree Yips – | 42 (81%) | 174 (96%) | |
| Dystonia Screening Questionnaire | Median | Median | |
| 0 (0–3) | 0 (0–5) |
[i] Legend table 1: HCP = Handicap, ex = former smoker, IU = International Units, p/w = per week, VAS = Visual Analogical Scale, OCT = Obsessive Compulsive Traits, NV = Not Valid because of insufficient numbers.