Table 4 summary of outcome measures and findings for each identified study

Bell and Thompson [18] Golfing Yips

Yip frequency, baseline, during 5 rounds of golf and at a 60-day follow-up

Physiological – observed yip frequency & Putting percentages.

Researcher read aloud the SGFI protocol to the participant prior to them putting.

Researcher (also, participant and playing partner recorded yip frequency and putting percentage)

Training not reported

Exposure to the SFGI reduced yip frequency from an average of 9.2 yips per round to 0.2 yips per round.

Only 1 yip occurrence was recorded during the intervention phase.

At baseline, the participant averaged 77 % putts within four feet compared with 97 % during the intervention phase.

The participant averaged 81 % of putts within four feet or less at the 60-day follow-up.

While the participant said that they felt more confident to putt after being exposed to SFGI, they were unsure why it had helped and were worried that their yips would reoccur.

100 % adherence

There was no control group to compare the findings, although the authors note that ‘each participant serves as their own control as participants’ performance is compared across baseline and intervention phases’ The study recruited only one participant and so no statistical power, generalisability or reliability.

Results open to reporter bias.

Yip type was unspecified.

Bell et al. [21] Golfing Yips

Yip occurrences were observed at baseline, during at least 5 treatment sessions of golf and at a 3-week follow-up golfing session after the last SFGI round.

Physiological – yip occurrences and percentage of putting with the yips.

1-2 independent observers were stationed at each site. The primary researcher read aloud the SFGI protocol to participants prior to them putting.

Primary researcher (also, 3 trained observers recorded putting behaviour and yip frequency)

Participant 1, BL yips 4, Reduced to 1.4, FU NR

Effect size, moderate (0.65).

Participant 2, BL yips 3, Reduced to 1.3 FU NR Effect size, moderate (0.55).

Participant 3, BL yips 3.6, Reduced to 0.8 FU NR Effect size, moderate (0.73).

(1 participant withdrew after completing four rounds of golf at baseline)

It is unclear whether the primary researcher was 1 of the 3 trained observers. Training provision was specified for the 3 observers but not for the primary researcher.

The study is underpowered because it reports on only 3 participants.

No control group to compare.

No reported p values.

The author’s note that no attempt was made to exclude Type I or Type II yips and so some or all of the participants may have been living with secondary yip dystonia.

Bell et al. [22] Golfing Yips

Yip frequency was measured at baseline, immediately after treatment and at follow-up (12–14 weeks post-treatment).

Physiological – symptom severity, looking at the frequency of yip occurrences. Observations of the golfers putting were video-recorded.

Individual/1 facilitator read aloud the SGFI protocol to each participant and then recorded the participant’s answers 15 min prior to them putting.

Trained facilitators (individual/1 facilitator per participant).

100 % of participants showed a decrease in the frequency of yip behaviour:

At baseline (average Mean of yip frequency):

2.86

Treatment stage (average Mean of yip frequency): 0.68

Maintenance - at least 12 weeks from treatment stage (average Mean of yip frequency): 0.08.

Effect sizes reported as either ‘large’ or ‘medium’ for baseline and treatment and baseline and maintenance.

100 % Adherence

The study is underpowered because it reports on only 4 participants.

No control group to compare.

No reported p values.

Boyce et al. [23] Cervical dystonia (neck dystonia)

Baseline (week 0), during treatment (week 6), post-treatment (week 12) and at a 4-week follow-up (week 16).

Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)

Participants video-recorded and 2 neurologists masked to treatment allocation evaluated symptom severity (primary outcome).

Self-rated pain and disability. Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) (secondary outcomes).

depression and quality of life

The Beck Depression Inventory Craniocervical Dystonia Questionnaire 24 (secondary outcomes).

Cervical range of motion was recorded using a Cervical Range of Motion device (secondary outcome).

Attendance at the physiotherapy sessions, adverse effects and muscle soreness were also documented. Participants completed diaries

Intervention:

‘Active neck exercises plus [whole body] relaxation’

Control: Whole body relaxation programme

Physiotherapist (individual/supervised physiotherapy sessions)

Participants were also encouraged to practise exercises at home

No mention of training

No adverse effects reported. Mild muscle soreness was reported in 66 % of the sample.

No significant differences between intervention and control group at treatment and follow-up phases.

The intervention group showed an (non-significant) improvement in depression scores compared to the control group in week 12 and ‘a greater (non-significant) improvement in TWSTRS’ in weeks 12 and 16 (p. 6).

Effect size: −1.9 (reported difference between the intervention and control groups on TWSTRS).

The physiotherapy and home exercise sessions were ‘well-adhered to by both groups’

Adherence

78 % intervention

91 % control

Small sample and effect size.

Confounding variable: N = 7 received Botulinum Toxin therapy injections which may have reduced the effect size.

No results were found to be significant. The authors note that the Cervical Range of Motion instrument has unknown reliability for people with cervical dystonia and head tremor/jerks.

Cottraux et al. [25] Writer’s cramp (hand dystonia)

Writing quality was observed at baseline (pre)-intervention), post-intervention (last session) and follow-up (at varying weeks between 1 to 9 months).

Participants copied a standardised piece of text in the clinic and recorded the amount of cramps they experienced.

An independent evaluator also rated participants’ frequency of spasms, writing improvement and writing quality using 3 separate scales across baseline, treatment and follow up phases.

‘Relaxation, and/or systematic desensitisation (SD), and/or assertiveness training through role playing were combined with Electromyography (EMG) feedback’ (2 participants were not given EMG feedback) (P. 182)

Unspecified but participants were referred to authors’ department

No mention of training

69 % of the sample (N = 9) showed improvements in writing at follow-up (time at follow-up varied between participants, ranging from 1 to 9 months)

Of the 4 participants who withdrew during the treatment phase, 3 showed an improvement in handwriting.

Adherence

60 % (2 participants refused treatment and 4 withdrew during the treatment phase)

Small sample size.

Limited results and follow-up data to draw meaningful conclusions.

7 participants were reported as presenting with severe mental health problems prior to data collection.

2 participants felt depressed or worried despite showing an improvement on the handwriting scale.

1 participant was described as having ‘’normal handwriting’ out of the 69 % who reported an improvement

Faircloth and Reid [24] Cervical dystonia (neck dystonia)

Measures were conducted at baseline (pre-treatment), post-treatment and at one, three and six month follow-ups.

The participant was asked to record, using visual analogue scales, how many times they spent worrying about the physical and emotional aspects of their dystonia.

The Beck Depression Inventory and the Beck Anxiety Inventory measured the participant’s overall psychological health.

Enabling self-focus, generating adaptive beliefs and challenging negative thinking.

Unspecified

Improvements were noted in psychological well-being (i.e., anxiety and depression). Pain and discomfort in the participant’s neck was reported as less severe. All of the participant’s 6 months follow-up scores were lower than at baseline.

Small study (N = 1) and so not statistically generalisable.

Only subjective (validated and unvalidated) self-report measures were used.

Greenberg [26] Writer’s cramp (hand dystonia)

Measures were conducted at baseline (pre-treatment), 1 month, 6 months and various time periods between 2 and 6 years.

Patient and therapist independently rated how severely the patient’s problem affected their everyday life and how it impacted on their ability to achieve their targets.

Patients were observed during the clinic to assess their writing rate.

The patient measured their writing abilities outside of the clinical hospital and where possible a friend or relative confirmed the findings.

Fear and anxiety were also rated using general, validated measures.

A combination of ‘habit reversal, in vivo exposure and re-education’ [apart from 1 participant] Awareness training, encouragement from relatives and homework practice were also given.

Nurse therapists,

family and friends supervised homework practice and offered encouragement

the nurse therapists received 1–2 sessions of teaching in habit reversal therapy

The treatment showed an improvement in writing skills at least until the 6-months follow-up phase (p. 297).

All 4 participants responded to the treatment.

1 participant relapsed after stopping habit reversal practice.

100 % Adherence

Small sample size.

Not all of the measures were observed. An independent assessor did not assess tidiness.

Therapists only observed handwriting in artificial settings.

‘The habit reversal adopted in this trial – extension of the wrist, fingers, and thumb – inevitably means that the pen is released for 5 s. The spasm could thus be said to be rewarded by avoidance’

1 participant was reported as experiencing high levels of anxiety.

Sharpe [28] Blepharospasm (eye dystonia)

Unspecified, baseline, treatment and 9 months follow-up

Relaxation (exercise) training for the eyelids, learning not to force the eyelids open and seeking rewarding reinforcements for keeping the eyelids open

Unspecified

Outcomes included reduction of eyelid spasm and ache as well as relaxation of the eyelids.

Participant was able to control spasms and resume daily social and business activities.

No deterioration was reported at the 9-months follow-up.

100 % Adherence

Small study (N = 1) and so not statistically generalisable.

Minimal description of follow-up procedures or outcome measures.

Wieck et al. [27] Writer’s cramp (hand dystonia)

Outcome measures were recorded at baseline (pre-treatment, weeks 0 and 4), post-treatment (week 8) and at a 3 months follow-up (week 20).

‘Observation of writing within the session, assessment of writing tasks completed at home, and blind ratings by an independent assessor’

Patients were educated to know when their symptoms were triggered and to immediately respond (e.g., by putting down the pen) until their cramp stopped. Severer participants were asked to draw lines proceeding to more complex shapes and finally, words.

Control group trained to practice ‘progressive relaxation technique’ (p. 113).

2 therapists

No mention of training

No significant differences were reported between the intervention and control groups on 89 % of the measures.

There was an increase in the frequency of words written at home among the relaxation group than with the habit reversal group (where there was a slight decrease).

Both groups improved significantly ‘in legibility, number of interruptions, and the ratings for problem severity, pain and difficultly’ (p. 114).

However, this was only slightly and participants ‘remained substantially handicapped’ with regards to writing speed (p. 114).

The authors conclude that they found no evidence to suggest that habit reversal treatment is more effective than general relaxation.

Adherence

82 % intervention

92 % control

Small sample size.

N = 1 experienced anxiety and avoidance behaviour and N = 3 experienced generalised anxiety