PURPOSE: Coccygodynia is a painful condition localized in the region of the coccyx. Most cases of coccygodynia are treated conservatively. However, we conducted an analysis of patients who underwent coccygectomy, with chronic intractable coccygodynia and assessed the results of their treatment. MATERIALS AND METHODS: From March 2003 to August 2013, this study was conducted in order to investigate the benefit of coccygectomy in cases where conservative treatment has failed. We compared preoperative and postoperative visual analog scales (VAS) scores and confirmed duration of symptom free, complications. RESULTS: The average duration of symptom free was 3.4 months, and VAS score improved from 7.3 to 1.6. There was one wound infection. CONCLUSION: We can obtain satisfactory results through coccygectomy for chronic intractable coccygodynia.
Coccyx ; Humans ; Visual Analog Scale ; Wound Infection

OBJECTIVETo describe the design and application of cluster randomized controlled method on typhoid Vi vaccine trial, and to assess the effect of implementation.

METHODSSimple size calculation of cluster-randomized trial was used to determine the sample size of the two groups and a vaccination campaign was conducted. The study group was given typhoid Vi vaccine and the control group was given meningococcal A vaccine.

RESULTSAccording to sample size calculation, a total sample of 96,121 participants was required and the study areas were divided into 108 clusters. In practice, 53 study clusters with 44,054 participants and 54 control clusters with 48,422 participants were stratified and matched according to size, location (urban or rural), characteristics (school, department, factory, demography) were randomized respectively. Confounding factors of two groups including age, sex, resident area, income, level of education were compared. It was found that the ratio of all confounding factors between the two groups were comparable and balanced.

CONCLUSIONConfounding factors can be better controlled between study group and the control group by applying cluster-randomized method on vaccine trail which enabled the intervention to be more scientifically evaluated; The implementation of cluster randomization trial was simple and easy to be accepted.

Adolescent ; Adult ; Child ; Child, Preschool ; China ; Cluster Analysis ; Female ; Humans ; Male ; Mass Vaccination ; organization & administration ; Middle Aged ; Polysaccharides, Bacterial ; immunology ; Typhoid Fever ; prevention & control ; Typhoid-Paratyphoid Vaccines ; immunology ; Vaccination

OBJECTIVETo evaluate the safety of a group A + C meningococcal polysaccharide vaccine as part of a phase IV clinical trial.

METHODSThe study area was divided into 108 clusters according to the principle of cluster randomization, stratified and paired sampling methods. 54 out of 108 clusters served as observation groups were administered A + C vaccine, while the rest 54 groups were administered Vi polysaccharide vaccine. An adverse event surveillance system was established to monitor the adverse events following the vaccination campaign. Identical form and methods were used for data collection to investigate the adverse events following the vaccination of both A+ C vaccine and Vi vaccine.

RESULTS34,543 people were vaccinated, including 18,167 of whom received A + C vaccine, while the other 16,376 received Vi vaccine. The rates of immediate injection reaction and unsolicited non-serious adverse events from A + C vaccine group were 0.44% and 0.38% while of Vi vaccine group were 0.79% and 0.73% respectively. At the solicited adverse event survey on 3-day-post-vaccination, 1239 vaccinees were followed-up including 771 received A + C vaccine and 468 received Vi vaccine. The local injection reaction rate of A + C vaccine group on the 1st day was significantly higher (X2 = 13.98, P = 0.0002) than that of Vi vaccine group. Neither the local injection reaction rate nor the system reaction rate between both groups was significantly different on 2nd and 3rd day, post vaccination. It was not statistically different when comparing fever onset rate between those who received vaccine and those who did not, in each vaccine group. There were no serious adverse events observed.

CONCLUSIONResults showed that the side effects of A + C vaccine and the Vi vaccine were mild and safe for vaccination campaigns targeting on populations at different age.

Adolescent ; Adult ; Age Distribution ; Child ; Child, Preschool ; Female ; Humans ; Male ; Meningococcal Vaccines ; adverse effects ; immunology ; Middle Aged ; Polysaccharides, Bacterial ; immunology ; Sex Distribution ; Young Adult