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Chapter 12
Questionnaires
Patients were asked to fill in questionnaires before discharge and 24 hours later by telephone
call. The questionnaires for patients (Patient Satisfaction with Sedation Instrument (PSSI))
and endoscopists (Clinical Satisfaction with Sedation Instrument (CSSI)) were developed
by Vargo et al.
25
and translated into Dutch by our own research group. The PSSI contains
4 subscores to describe patient satisfaction. The most relevant are the two subscores
about sedation side effects and global satisfaction. The CSSI also has 4 subscores with one
subscore relevant for global satisfaction. In these questionnaires, patients and endoscopists
could classify their satisfaction or dissatisfaction during the procedure ranging from 7 =
very satisfied to 1 = very dissatisfied.
25
Pain was assessed post-procedurally by means of a
numeric rating scale (NRS) reaching from 0 = no pain to 10 = worst pain.
Statistical methods
Sample size calculation was based on observational propofol data from previous
colonoscopies collected in our hospital sedation database. The mean dosage of propofol
during colonoscopy in this database was 441±176 mg (mean ± SD).
26
Given a power of 0.80
and a type I error of 0.05 to reduce propofol dosage by 25 %, we had to include 47 subjects
in each group to show significance. Considering a dropout rate of 10 %, the estimated
sample size was 51 patients per group.
Statistical analyses were performed using SPSS statistics (version 23.0). All data was checked
for normal distribution using the Kolmogorov test, Q-Q plot and histogram. For normal
distributed, continuous variables an One-way ANOVA was used and the variables are
presented as mean ± standard deviation (SD). For normal distributed categorical variables
Pearson’s chi-squared test was applied and variables were allegorised as number and/or
percentage. Not normally distributed data were compared using the multifactorial ANOVA
(Kruska Wallis). These variables are presented as median and interquartile range (IQR). A
p-value < 0.05 was considered statistically significant.
RESULTS
In total, 222 patients were assessed for eligibility; 69 patients were not willing to participate
or were excluded for other reasons. The remaining 153 patients were allocated randomly
to receive electro-acupuncture (group EA, n=51), sham-acupuncture (group SA, n=51), or
placebo acupuncture (group PA, n=50). In the PA group, we excluded one patient from
analysis due to incomplete data collection. The study flow chart is shown in Figure 2.
All three groups were comparable with regard to their baseline characteristics, indication
for and length of the colonoscopy procedure (Table 1).