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At least 19 recordsLinked to original sources
PubMed2005

Challenges in herbal research: a randomized clinical trial to assess blinding with ginger.

OBJECTIVE: To assess methods to blind study participants to encapsulated ginger (Zingiber officinale). DESIGN: A randomized double-blind placebo controlled trial. SUBJECTS: Eighty healthy male and female volunteers. OUTCOME MEASURES: Whether participants can accurately determine if they receive a ginger or placebo capsule and a bottle filled with ginger or placebo capsules. RESULTS: Forty-two subjects correctly identified the capsule they received. Of those who received placebo, over 82% correctly identified their capsule. Only 22.5% of those who received ginger correctly identified their capsule. The likelihood of guessing ginger between the groups was statistically similar (p<0.01). 65% correctly guessed which bottle they had received (p=0.0073). Participants receiving the bottle filled with ginger capsules successfully identified their bottle 75% of the time (p=0.0016) compared to the 55% of the placebo group (p=0.5). CONCLUSIONS: Volunteers cannot determine which type of individual capsule they receive but can distinguish a bottle filled with ginger capsules.

Adult↗
PubMed2002

Endoscopic versus open carpal tunnel release in bilateral carpal tunnel syndrome. A prospective, randomised, blinded assessment.

The advantages and disadvantages of endoscopic compared with open carpal tunnel release are controversial. We have performed a prospective, randomised, blinded assessment in a district general hospital in order to determine if there was any demonstrable advantage in undertaking either technique. Twenty-five patients with confirmed bilateral idiopathic carpal tunnel syndrome were randomised to undergo endoscopic release by the single portal Agee technique to one hand and open release to the other. Independent preoperative and postoperative assessment was undertaken by a hand therapist who was blinded to the type of treatment. Follow-up was for 12 months. The operating time was two minutes shorter for the open technique (p < 0.005). At all stages of postoperative assessment, the endoscopic technique had no significant advantages in terms of return of muscle strength and assessment of hand function, grip strength, manual dexterity or sensation. In comparison with open release, single-portal endoscopic carpal tunnel release has a similar incidence of complications and a similar return of hand function, but is a slightly slower technique to undertake.

Activities of Daily Living↗
PubMed2005

Does metformin modify ovarian responsiveness during exogenous FSH ovulation induction in normogonadotrophic anovulation? A placebo-controlled double-blind assessment.

OBJECTIVE: To assess whether the addition of metformin to gonadotrophin ovulation induction in insulin-resistant, normogonadotrophic, anovulatory women alters ovarian responsiveness to exogenous FSH. DESIGN: Placebo-controlled double-blind assessment in an academic hospital. RESULTS: After a progestagen withdrawal bleeding, patients were randomised for either metformin (n = 11) or placebo (n = 9) treatment. In cases of absent ovulation, exogenous FSH was subsequently administered to induce ovulation. Only during metformin treatment did body mass index and androgen (androstenedione and testosterone) levels decrease, whereas FSH and LH levels increased significantly. In the metformin group, a single patient ovulated before the initiation of exogenous FSH. Significantly more monofollicular cycles and lower preovulatory oestradiol concentrations were observed in women receiving FSH with metformin compared with FSH alone. CONCLUSIONS: Metformin co-treatment in a group of insulin-resistant, normogonadotrophic, anovulatory patients resulted in normalization of the endocrine profile and facilitated monofollicular development during the FSH induction of ovulation.

Adolescent↗
PubMed2005

Patient knows best: blinded assessment of nonadherence with antituberculous therapy by physicians, nurses, and patients compared with urine drug levels.

BACKGROUND: Adherence with therapy is a wide spectrum of behavior rather than a categorical state. While extreme nonadherence is readily apparent, it is rare compared to lesser degrees of nonadherence, which are difficult to predict. AIMS: To compare the accuracy of doctor, nurse, and patient prediction of adherence with antituberculous therapy with urine isoniazid levels. METHODS: A prospective, blinded clinical study was conducted, comparing adherence to antituberculous therapy as reported by patients, doctors, and nurses with urine isoniazid levels. We studied 173 patients with active tuberculosis (TB) recruited over 3 years in two TB clinics in Victoria, Australia. Adherence was defined as six random urine isoniazid (INH) levels being >0. Blinded assessment of adherence was completed by doctors, nurses, and patients. Lid opening and closing of computerized pill bottles were measured in a random subsample. RESULTS: Of 173 patients, the rate of nonadherence was 24% (41/173) by urine INH, 54% (93/173) by patient self-report, 11% (19/173) by doctor assessment, and 7% (12/173) by nurse assessment. The sensitivity of prediction of nonadherence was 76% for patient self-report, 24% for doctor assessment, and 19% for nurse assessment. The 10 patients who used computerized pill bottles were all (100%) noncompliant at some stage. CONCLUSION: Nonadherence is common and poorly predicted by doctors and nurses, even those with extensive experience in treating TB. Contrary to popular belief, patient self-report is more reliable than doctor or nurse assessment of nonadherence. As clinicians, asking patients about adherence may be more valuable than attempting to judge for ourselves.

Antitubercular Agents↗
PubMed2005

Ziprasidone and haloperidol in the treatment of acute exacerbation of schizophrenia and schizoaffective disorder: comparison of intramuscular and oral formulations in a 6-week, randomized, blinded-assessment study.

RATIONALE: Conventional intramuscular (IM) antipsychotics used in managing acute exacerbation of schizophrenia are associated with side effects such as acute dystonia. OBJECTIVES: To compare the efficacy and tolerability of sequential IM/oral ziprasidone with haloperidol in acute exacerbation of schizophrenia or schizoaffective disorder. METHODS: In a 6-week, multicenter, parallel-group, flexibly dosed study, patients were randomized to ziprasidone (IM up to 3 days, then oral 40-80 mg, b.i.d.) or haloperidol (IM up to 3 days, then oral 5-20 mg/day). Assessments were rater-blinded. RESULTS: At the end of IM treatment, patients receiving ziprasidone (n=427) showed significantly improved Brief Psychiatric Rating Scale Total (BPRS total) scores compared with those receiving haloperidol (n=138) [least-squares (LS) mean change -6.14 for ziprasidone versus -4.13 for haloperidol, P<0.0018]. At endpoint, there were no significant between-group differences in BPRS total scores. There was a significantly greater improvement in BPRS negative subscale scores in ziprasidone-treated patients, both at the end of IM treatment (LS mean change -1.15 for ziprasidone and -0.28 for haloperidol, P<0.0001) and at study endpoint (LS mean change -2.94 for ziprasidone and -2.24 for haloperidol, P<0.0001). Haloperidol-treated patients exhibited significantly greater increases in Extrapyramidal Symptom Rating Scale at end of IM treatment and at endpoint (P<0.0001). They also had significantly higher ratings on the Barnes Akathisia Scale (P<0.0001) and the Movement Disorder Burden Score (P<0.005), as well as higher incidences of movement disorder-related adverse events. CONCLUSIONS: Sequential IM and oral ziprasidone offers important efficacy and tolerability advantages over haloperidol in acute schizophrenia.

Acute Disease↗
PubMed1991

Sedation for paediatric computerized tomography--a double-blind assessment of rectal midazolam.

This double-blind study investigated the rectal administration of midazolam as an alternative to general anaesthesia for elective computerized tomography (CT) of the brain. Thirty children were randomly allocated to receive either midazolam 0.3 mg kg-1 (Group 1) or midazolam 0.6 mg kg-1 (Group 2) by the rectal route. Sedation was obtained in 13 children in Group 1 and 12 in Group 2 but this was only satisfactory for scanning in seven children in Group 1 and eight in Group 2. We concluded that although the technique produced sedation, it did not reliably produce satisfactory conditions for CT scanning.

Administration, Rectal↗
PubMed1983

Double-blind assessment of stimulant medication for attention deficit disorder: a model for clinical application.

A double-blind procedure is presented for assessing the response to stimulant medication among children with attention deficit disorder. Of 94 children treated with methylphenidate and placebo, 70 demonstrated a positive response to active medication. It is suggested that a double-blind investigation is an efficient means of securing meaningful treatment information, particularly in difficult family or clinical situations.

Adolescent↗
PubMed2005

A blinded assessment of radiographic criteria for atlanto-occipital dislocation.

STUDY DESIGN: Blinded comparison of 5 methods to diagnose atlanto-occipital dislocation (AOD) on plain radiographs and computerized tomography (CT) of the cervical spine. OBJECTIVE: To determine the best method to diagnose AOD. SUMMARY OF BACKGROUND DATA: Several methods are proposed for the diagnosis of AOD, including the Power's ratio, X-line method, basion-dens interval, condylar gap, and Harris method. No blinded comparison of the results of these methods has been compared to patient outcome, and there is no information available regarding the accuracy of these methods applied to CT scans. METHODS: Plain lateral radiographs and CTs of the cervical spine were reviewed in 104 patients, including 6 with AOD. Images underwent a blinded review by a board certified neurosurgeon (D.K.R.), orthopedist (P.A.A.), radiologist (J.C.), and emergency physician (D.B.B.). Each diagnostic method for AOD was applied for determination of sensitivity, specificity, and positive and negative predictive values. The ability to identify relevant anatomic landmarks was also tabulated. RESULTS: Average values for sensitivities, specificities, positive and negative predictive values for each method applied to plain radiographs are: 0.4625-1.0, 0.8933-0.9725, 0.2775-0.45, and 0.975-1.0, respectively. These values for each method applied to CT scans are: 0.7075-1.0, 0.8725-0.9775, 0.3175-1, and 0.98-1.0, respectively. Identification of relevant anatomic landmarks occurred 99.75% of the time when these methods were applied to CT scans compared to 39% to 84% of the time on plain radiographs. CONCLUSIONS: Sensitivity, specificity, positive and negative predictive values of these methods improve when applied to CT scans because of better visualization of anatomic landmarks. This result suggests CT scans of the cervical spine may be warranted in all trauma patients suspected of having cervical spine injury.

Atlanto-Occipital Joint↗
PubMed1981

Double-blind assessment of the activity of minaprine (30038-CB) in child psychiatry.

A double-blind, crossover trial was carried out in 26 children with psychiatric disorders to assess the effectiveness of treatment with minaprine (100 mg per day) or placebo, each treatment being given in random order for 4 weeks. Patients were assessed before treatment and at 14 day intervals using a modified 34-item Hamilton rating scale. The results showed a definite therapeutic superiority of minaprine over placebo and a good response was achieved in over 50% of the children, including those showing signs of the "hyperactive syndrome'. Minaprine was well tolerated by all the patients.

Adolescent↗
PubMed1993

Pain relief after arthroscopic surgery of the knee: a prospective, randomized, and blinded assessment of bupivacaine and bupivacaine with adrenaline.

A prospective, randomized, and double-blind study was conducted to compare the influence on postoperative pain of equal volumes of saline, bupivacaine, or bupivacaine with adrenaline, injected both intraarticularly and into the wound puncture site, for 118 day case patients undergoing elective knee arthroscopy. Marginal analyses of postoperative visual analogue pain scores and postoperative fentanyl doses showed that the group given bupivacaine with adrenaline had less postoperative pain when compared with the saline group. However, when multifactor analyses were performed, preoperative visual analogue pain scores, operation type and length, and the sex of the patient were all shown to be significant predictors of postoperative pain, but the use of bupivacaine was not. We conclude that the observed differences in postoperative pain were due to differences between the groups in these predictive factors, especially preoperative pain scores, and that the use of bupivacaine was less important and not statistically significant in influencing postoperative pain.

Adult↗
PubMed1976

A 12-month double-blind assessment of betamethasone valerate aerosol in the management of asthma.

A double-blind trial of the topically active corticosteroid, betamethasone valerate in aerosol form, in the control of chronic asthma is reported. The results show that this is an extremely effective therapeutic agent in non-steroid dependent but nonetheless moderately severe asthmatics. Patients were well controlled on 800 mug of betamethasone valerate daily and control was maintained over a 12-month period. This form of treatment has few undersirable side effects but there is probably an increased incidence of oropharyngeal and laryngeal candidiasis. In particular, adrenocortical suppression was not noted.

Adolescent↗
PubMed1999

Agreement between 'time-blind' and 'time-non-blind' assessments of depressive symptomatology.

In a 4-week study, two methods were used simultaneously in the assessment of depressive symptomatology with videotaped structured clinical interviews: a 'time-non-blind' (TNB) method (chronological order, observer aware of the previous duration of drug treatment) and a 'time-blind' (TB) method (no chronological order, rater unaware of the previous duration of treatment). Sixty newly admitted depressed inpatients with Montgomery-Asberg Depression Rating Scale scores higher than 20 were assessed before (D0), after 10 days (D10) and after 28 days (D28) of antidepressant treatment. Agreement between TNB and TB methods on the Montgomery-Asberg Depression Rating Scale, measured by intra-class correlation coefficients, was good at D0 (0.68), excellent at D10 (0.81) and D28 (0.86), but not significantly different between D0, D10 and D28. The statistical method of Bland and Altman (1986) was also used to evaluate the degree of agreement. Results of this second analysis were in accordance with the intra-class correlation coefficient results, and showed significantly (P < 0.05) higher D0-D28 and D10-D28 intrasubject changes with the TB method, which were largely accounted for by some particular items (inner tension, pessimism, lassitude). With the Clinical Global Impression-Severity score, the Bland and Altman method failed to show significant differences between the two methods, and compared with the Montgomery-Asberg Depression Rating Scale, intra-class correlation coefficients were lower with larger confidence intervals, suggesting that global ratings are less reliable than itemized symptom ratings.

Adolescent↗
PubMed1978

Comparison of blind and non-blind assessments of occlusal sealant retention.

A comparison was made of scoring the retention status of BIS-GMA occlusal sealants 5 years after they had been placed, according to a non-blind and blind method of identification of teeth that had been sealed. Subjects were 175 children ages 15--18. One examiner made all the assessments. Retention of sealant was classified as all present, partly missing or all missing. There was 90.5% complete agreement between non-blind and blind examinations in scoring the retention status of 893 occlusal sites. Essentially no difference in agreement was found between sites on maxillary and mandibular teeth nor according to sites in specific teeth. There was only a slight tendency to classify more sites as having sealant present at the non-blind examinations than at the blind examinations, 56.7% and 55.1%, respectively. These findings would seem to indicate that whether examinations are done blindly or non-blindly is of minor importance in making an accurate assessment of sealant retention.

Adolescent↗
PubMed1986

How blind is blind? Assessment of patient and doctor medication guesses in a placebo-controlled trial of imipramine and phenelzine.

The purpose of the double blind is to protect the internal validity of a clinical trial by preventing knowledge of treatment conditions from influencing outcome or its assessment. We studied medication guesses of 137 depressed patients and/or their doctors at the end of a 6-week randomized trial of placebo, imipramine, and phenelzine. Overall, 78% of the patients and 87% of the doctors correctly distinguished between placebo and active medication. Clinical outcome, treatment condition, and their interaction each contributed to guessing accuracy, while medication experience and side effects assessed only in week 6 did not. Accuracy was high, however, even when cases were stratified for clinical outcome, indicating that other cues were available to the patients and doctors. These may include patterns and timing of side effects and clinical response not detectable in this end-point analysis.

Adolescent↗
PubMed1989

Double-blind assessment of the value of magnetic resonance imaging in the diagnosis of anterior cruciate and meniscal lesions.

A prospective double-blind study was undertaken to evaluate the usefulness of magnetic resonance imaging in the accurate interpretation of pathological intra-articular changes in the knee. Forty-seven patients who were scheduled to have arthroscopy and three patients who wer to have arthrotomy volunteered for magnetic resonance imaging preoperatively. The radiologists had no clinical or roentgenographic information about the patients before the evaluation of the magnetic resonance images, and the radiologists' interpretations were unknown to the surgeon before the arthroscopy or arthrotomy was done. Our important observations were limited to the findings in the menisci and in the anterior cruciate ligament. Magnetic resonance imaging had a positive predictive value of 75 per cent, a negative predictive value of 90 per cent, a sensitivity of 83 per cent, and a specificity of 84 per cent for pathological findings in the menisci. For complete tears of the anterior cruciate ligament, the positive predictive value was 74 per cent; the negative predictive value, 70 per cent; the sensitivity, 61 per cent; and the specificity, 82 per cent. We believe that magnetic resonance imaging, when combined with clinical and roentgenographic examination, provides the most accurate non-invasive source of information that is currently available for pathological findings in the menisci and in the anterior cruciate ligament.

Adolescent↗
PubMed1997

A double-blind assessment of the analgesic sparing effect of intrathecal diamorphine (0.3 mg) with spinal anaesthesia for elective caesarean section.

In a randomized double-blind study, 40 healthy women undergoing elective caesarean section with spinal anaesthesia received either 0.3 mg diamorphine or saline with bupivacaine 0.5% in 8% dextrose. The study recorded time to the first morphine demand delivered by patient-controlled analgesia (PCA), and total morphine requirement over 24 h. In addition pain, sedation, and pruritus were assessed by non-graduated visual analogue scores (VAS). Six patients in the diamorphine group required no postoperative morphine. The median (interquartile range) time to first morphine demand was significantly longer in the diamorphine group at 340 min (127, never used), than in the control group at 80 min (53, 159) (P 0.0006, 95% confidence interval for the difference between the medians is 60 to 1235 min). The use of PCA morphine over 24 h was significantly less in the diamorphine group than in the controls. The medians (interquartile ranges) were 5 (0, 36) mg vs 45 (26, 72) mg (P 0.0045, 95% confidence interval for the difference between the medians is 12 to 46 mg). In the diamorphine group, postoperative VAS for pain was significantly lower at 2 h and 3 h both at rest (P 0.0003, 0.003) and on moving (P 0.009, 0.002), at 8 h on moving (P 0.01), and at 12 and 24 h at rest (P 0.005, 0.029). Significantly more women suffered pruritus in the diamorphine group for the first 12 h after surgery (P 0.01).

Clinical Trial↗