Cent Cent Confidence Intervals Research Articles

Effect of orthodontic treatment on periodontal clinical attachment: a systematic review and meta-analysis.

Insertion of orthodontic fixed appliances has been known to induce a mostly transient qualitative and quantitative alteration of the intraoral microbiota. However, the extent to which treatment with fixed appliances might have a lasting adverse effect on the periodontal attachment of the teeth has not yet been investigated in an evidence-based manner. Aim of this systematic review was to assess the effect of comprehensive treatment with fixed orthodontic appliances on clinical attachment levels of adolescent and adult periodontally healthy patients. Seven databases were searched from inception to February 2017. Prospective non-randomized longitudinal clinical studies. After duplicate study selection, data extraction, and risk of bias assessment according to the Cochrane guidelines, Paule-Mandel random-effects meta-analyses of the clinical attachment loss and its 95 per cent confidence intervals (CIs) were calculated. A total of 9 trials were identified that included 335 treated patients (at least 34 per cent male / 66 per cent female) with an average age of 22.6 years. The average pooled clinical attachment loss was 0.11 mm (9 studies; 335 patients; 95 per cent CI = 0.12 mm gain to 0.34 mm loss; P = 0.338) with high heterogeneity. Furthermore, one study hinted that a small amount of clinical attachment might be gained by intrusion of upper incisors. Additional analyses indicated that the results were robust to addition of untreated patient groups, while patient age and timing of outcome measurement might play an important role. According to existing evidence from longitudinal clinical studies orthodontic treatment with fixed appliances has little to no clinically relevant effect on periodontal clinical attachment levels. PROSPERO (CRD42017057042). None.

Volumetric upper airway changes after rapid maxillary expansion: a systematic review and meta-analysis.

Although Rapid Maxillary Expansion (RME) has been used for over a century, its effect on upper airways has not yet adequately been assessed in an evidence-based manner. To investigate the volumetric changes in the upper airway spaces following RME in growing subjects by means of acoustic rhinometry, three-dimensional radiography and digital photogrammetry. Literature search of electronic databases and additional manual searches up to February 2016. Randomized clinical trials, prospective or retrospective controlled clinical trials and cohort clinical studies of at least eight patients, where the RME appliance was left in place for retention, and a maximum follow-up of 8 months post-expansion. After duplicate data extraction and assessment of the risk of bias, the mean differences and 95 per cent confidence intervals (CIs) of upper airway volume changes were calculated with random-effects meta-analyses, followed by subgroup analyses, meta-regressions, and sensitivity analyses. Twenty studies were eligible for qualitative synthesis, of which 17 (3 controlled clinical studies and 14 cohort studies) were used in quantitative analysis. As far as total airway volume is concerned patients treated with RME showed a significant increase post-expansion (5 studies; increase from baseline: 1218.3mm3; 95 per cent CI: 702.0 to 1734.6mm3), which did not seem to considerably diminish after the retention period (11 studies; increase from baseline: 1143.9mm3; 95 per cent CI: 696.9 to 1590.9mm3). However, the overall quality of evidence was judged as very low, due to methodological limitations of the included studies, absence of untreated control groups, and inconsistency among studies. RME seems to be associated with an increase in the nasal cavity volume in the short and in the long term. However, additional well-conducted prospective controlled clinical studies are needed to confirm the present findings. None. Australian Society of Orthodontics Foundation for Research and Education Inc.

Healthcare and aging: do European Union countries differ?

Purpose The purpose of this paper is to evaluate socio-economic inequalities in the use, accessibility and satisfaction with health services amongst 60-84 year old people from seven European urban communities. Design/methodology/approach Data for this study were collected in 2009. The target population was people aged 60-84 years from Stuttgart (Germany), Athens (Greece), Ancona (Italy), Kaunas (Lithuania), Porto (Portugal), Granada (Spain) and Stockholm (Sweden). The total sample comprised 4,467 respondents with a mean response rate across these countries of 45.2 per cent. Findings The study demonstrated that the majority of respondents had contact with a health care provider within the last 12 months. The highest percentages were reported by respondents from Spain (97.8 per cent) and Portugal (97.7 per cent). The results suggest that 13.0 per cent of respondents had refrained from seeking care services. The highest rates were amongst seniors from Lithuania (24.0 per cent), Germany (16.2 per cent) and Portugal (15.4 per cent). Logistic regression suggests that seniors who refrained from seeking health care was statistically significant associated with those with higher levels of education (odds ratios (OR)=1.21; 95 per cent confidence intervals (CI)=1.01-1.25) and financial strain (OR=1.26; 95 per cent CI=1.16-1.37). Furthermore, the majority of respondents were satisfied with health care services. Originality/value The findings from the "Elder Abuse: a multinational prevalence survey" study indicate the existence of significant variations in use, accessibility and satisfaction with health services by country and for socio-economic factors related to organizing and financing of care systems.

Clinical effects of pre-adjusted edgewise orthodontic brackets: a systematic review and meta-analysis

Fixed-appliance treatment is a major part of orthodontic treatment, but clinical evidence remains scarce. Objective of this systematic review was to investigate how the therapeutic effects and side-effects of brackets used during the fixed-appliance orthodontic treatment are affected by their characteristics. SEARCH METHODS AND SELECTION CRITERIA: We searched MEDLINE and 18 other databases through April 2012 without restrictions for randomized controlled trials and quasi-randomized controlled trials investigating any bracket characteristic. After duplicate selection and extraction procedures, risk of bias was assessed also in duplicate according to Cochrane guidelines and quality of evidence according to the Grades of Recommendation. Assessment, Development and Evaluation approach. Random-effects meta-analyses, subgroup analyses, and sensitivity analyses were performed with the corresponding 95 per cent confidence intervals (CI) and 95 per cent prediction intervals (PI). We included 25 trials on 1321 patients, with most comparing self-ligated (SL) and conventional brackets. Based on the meta-analyses, the duration of orthodontic treatment was on average 2.01 months longer among patients with SL brackets (95 per cent CI: 0.45 to 3.57). The 95 per cent PIs for a future trial indicated that the difference could be considerable (-1.46 to 5.47 months). Treatment characteristics, outcomes, and side-effects were clinically similar between SL and conventional brackets. For most bracket characteristics, evidence is insufficient. Some meta-analyses included trials with high risk of bias, but sensitivity analyses indicated robustness. Based on existing evidence, no clinical recommendation can be made regarding the bracket material or different ligation modules. For SL brackets, no conclusive benefits could be proven, while their use was associated with longer treatment durations.

Endovascular treatment of very small (≤ 3 mm) intracranial aneurysms: An updated systemic review

Aim: Previously‐published meta‐analyses have concluded that coil embolization of very small (≤ 3 mm) intracranial aneurysms carry a high risk of procedural rupture, leading to morbidity and mortality. Several case series subsequently questioned the real procedural rupture risk. We therefore carried out an updated meta‐analysis.Patients and Methods: Computerized EMBASE, MEDLINE and PubMed searches of the literature for reports on the safety and efficacy of treatment of intracranial aneurysms with a maximum dimension of ≤ 3 mm were carried out from January 1990 to January 2011. Statistical analyses were generated using SPSS for Windows Version 15.0 and Comprehensive MetaAnalysis 2.0 for Windows. Results of the meta‐analyses are presented with 95 per cent confidence intervals (CI).Results: Twelve eligible studies with 637 patients (660 aneurysms) were analysed. Procedural aneurysm rupture occurred in 39 (5.9 per cent) of 660 aneurysm treatments (random‐effect‐weighted average: 7.2 per cent; 95 per cent CI: 5.3–9.6 per cent; Q‐value: 11; I2 = 4 per cent). Immediate satisfactory occlusion was achieved in 508 (88 per cent) of 579 aneurysm treatments (random‐effect‐weighted average: 84 per cent; 95 per cent CI: 81–87 per cent; Q‐value: 48; I2 = 81 per cent). Delayed satisfactory occlusion was achieved in 379 (88 per cent) of 433 aneurysm treatments (random‐effect‐weighted average: 82 per cent; 95 per cent CI: 77–86 per cent; Q‐value: 48; I2 = 83 per cent).Conclusions: The present findings suggest that coiling of very small intracranial aneurysms is associated with 7.2 per cent procedural aneurysm rupture risk. Further prospective multicenter studies should be carried out in Hong Kong to review the procedural morbidity and mortality.

Work-Related Violence, Debriefing and Increased Alcohol Consumption among Police Officers

Purpose: this study examined the associations between increased alcohol consumption and work-related violence among police officers. Data consisted of a representative sample of Finnish police officers (N = 1,734), who responded anonymously to a postal questionnaire. Methods: binary logistic regression analyses were used to calculate the odds ratios and their 95 per cent confidence intervals (CIs) for increased alcohol consumption. Results: 5 per cent of the study group rated that they had increased their alcohol consumption due to violence. The odds ratios of the increase were 6.96 (95 per cent CI = 2.08–23.25) for lack of debriefing, 2.18 (95 per cent CI = 1.26–3.78) for shortage of patrol personnel, and 1.71 (95 per cent CI = 1.11–2.62) for lack of training to handle violent situations. Conclusions: those who lacked debriefing, patrol personnel, and training to handle violent situations all seem to increase their alcohol use due to violence. Increased alcohol consumption may reflect attempts to cope with some intolerable emotions or situations originating from violent encounters in their work.

Estimation of Expected Operational Losses: Approaches Based on Heavy Right-Tailed Distributions

This paper employs methodologies that were developed for heavy right-tailed distributions to construct the point and interval estimates of the expected operational losses in the US. These are consistent and unbiased estimates of the mean of the heavy right-tailed loss distribution, whereas those based on normal approximations are not reliable. The estimation methodologies used in this paper exploit the nature of the tail index that measures the degree of tail thickness. To eliminate the small-sample bias in the widely used Hill index estimator, this paper employs an estimator, which is the weighted average of Hill estimators. Furthermore, we employ both m out of n bootstrap and empirical likelihood methods for constructing reliable 95 per cent confidence intervals (CI) for the mean. We provide step-by-step details to show that how these methodologies are applied in practice. The results indicate that the estimates of the expected operational losses of financial institutions in the US are much bigger than the simple sample averages. The 95 per cent CI estimates of the expected losses are asymmetric and much wider than those based on normal approximations. These findings have implications for risk management and economic capital requirements.

Inference by eye: Reading the overlap of independent confidence intervals

When 95 per cent confidence intervals (CIs) on independent means do not overlap, the two-tailed p-value is less than 0.05 and there is a statistically significant difference between the means. However, p for non-overlapping 95 per cent CIs is actually considerably smaller than 0.05: If the two CIs just touch, p is about 0.01, and the intervals can overlap by as much as about half the length of one CI arm before p becomes as large as 0.05. Keeping in mind this rule-that overlap of half the length of one arm corresponds approximately to statistical significance at p = 0.05-can be helpful for a quick appreciation of figures that display CIs, especially if precise p-values are not reported. The author investigated the robustness of this and similar rules, and found them sufficiently accurate when sample sizes are at least 10, and the two intervals do not differ in width by more than a factor of 2. The author reviewed previous discussions of CI overlap and extended the investigation to p-values other than 0.05 and 0.01. He also studied 95 per cent CIs on two proportions, and on two Pearson correlations, and found similar rules apply to overlap of these asymmetric CIs, for a very broad range of cases. Wider use of figures with 95 per cent CIs is desirable, and these rules may assist easy and appropriate understanding of such figures.

Prediction of arch length based on intercanine width

Arch length (AL), intercanine width (ICW), and intermolar width (IMW) are essential for diagnosis and treatment planning and are closely related factors in orthodontics. The aim of the present study was to determine correlations between these measurements and to predict some of these measurements based on others. The dental casts of 197 Spanish patients (119 females and 78 males) with a mean age of 18 years (11-26 years) in the permanent dentition attending the Orthodontic Department of the University of Valencia, Spain, were selected. ICW, IMW, and AL on each dental cast were measured using a previously tested digital method. Correlation between variables was determined using Pearson's correlation coefficient. Linear regression analysis was applied and the 95 per cent confidence intervals (CIs) for slope and intercept were determined. The data showed very high correlations between ICW and AL, both for the upper and lower arches and for males and females, r = 0.925. This coefficient was very close to 1, indicating a linear relationship. The regression equation for AL and ICW was AL = 1.36 ICW + 29.39 for both arches. There was very high correlations between AL and ICW for the upper and lower arches and a regression equation between both magnitudes was established indicating that the size of one factor can be predicted by knowing the other. For an increase of 1 mm in ICW, the AL increases approximately 1.36 mm with a 95 per cent CI (1.30-1.42).

Risk factors for anaesthetic‐related death in referred dogs

ANAESTHETIC mortality risk factors associated with anaesthetic-related death have been studied in canine populations in North American referral practices (Lumb and Jones 1973, 1984, Hosgood and Scholl 1998, Gaynor and others 1999). Mortality risks for canine referral populations undergoing anaesthetic have been documented at 0·5 to 1 per cent. Typically, these risks are higher than those documented in first-opinion practice (Clarke and Hall 1990, Dyson and others 1998). Factors associated with anaesthetic-related death in referred animals include poor patient health status, old age and belonging to a brachycephalic breed (Lumb and Jones 1973, Hosgood and Scholl 1998, Gaynor and others 1999). Only the study by Hosgood and Scholl (1998) adjusted the risks associated with specific factors for confounding variables, and found that increased risk was only associated with increasing age and poor patient health status. Assessment of risk factors in a canine referral practice population has not been published recently in the UK. The aims of this study were to identify major risk factors associated with anaesthetic-related mortality and to estimate the mortality risk in a single UK canine referral practice population. A case-control study was conducted retrospectively from dogs anaesthetised at the Queen Mother Hospital for Animals (QMHA), Royal Veterinary College (RVC), from the beginning of February 1999 until the end of April 2002. The study was nested in a cohort of all dogs that were anaesthetised using an inhalation agent at the RVC during the study period. The cohort was generated from the QMHA’s computer system, based on the inhalation agent administered. Cases were defined as anaesthetic-related deaths occurring within 48 hours of anaesthesia, in which anaesthesia could not be excluded from contributing to death. Cases were identified from case records and postmortem reports. Controls were randomly selected from the cohort of dogs anaesthetised at the RVC during the three-year period using a case:control ratio of 1:2. Potential risk factors assessed included patient health status (ASA [American Society of Anesthesiologists] grade 1 to 2 healthy or mild disease versus ASA grade 3 to 5 severe disease to moribund), age, premedication with acepromazine (ACP; Vericore), premedication with opioids (pethidine [Pethidine injection BP; Martindale Pharmaceuticals], morphine [Morphine sulphate injection BP; Martindale Pharmaceuticals], butorphanol [Torbugesic injection; Fort Dodge] or papaveretum [Papaveretum injection BP; Martindale Pharmaceuticals]), overall premedication (benzodiazepines [Diazemals; Dumex or Hypnovel; Roche] and/or opioids only, acepromazine and/or opioids), induction with thiopentone (Intraval Sodium; Merial Animal Health) or propofol (Rapiovet; Schering-Plough Animal Health), maintenance of anaesthesia with halothane (Halothane Vet; Merial Animal Health) or isoflurane (IsoFlo; Schering-Plough Animal Health) and duration of anaesthesia. Crude odds ratios (ORs) and 95 per cent confidence intervals (CIs) for the odds of anaesthetic-related death were calculated for the exposure variables. Either the chi-squared test or Fisher’s exact test was applied for categorical data and Student’s t test or Mann-Whitney U test was applied for continuous data (Kirkwood 1988). Risk factors significant at the 20 per cent level were taken forward for further evaluation in the multivariable analysis. Following exploratory stratification, logistic regression (STATA 7.0; Statcorp) was used, and the contribution of the explanatory variables to the model was assessed. Statistically significant variables (P<0·05) were retained in a logistic regression model using a forward stepwise approach. Fit of the model was evaluated using the Hosmer-Lemeshow statistic (Hosmer and Lemeshow 1989). The anaesthetic-related mortality risk was estimated from the number of cases divided by the number of anaesthetics undertaken during the year from April 2001 to April 2002. During the three-year period, 6026 dogs were anaesthetised and 20 anaesthetic-related deaths were recorded. The anaesthetic-related death risk in the referral population for the year April 2001 to April 2002 was 0·58 per cent (one in 173 dogs; 95 per cent CI 0·24 to 0·92). The median ages (interquartile range) of cases and controls were 6·8 (3·8 to 10) and 5·9 (1·5 to 9·8) years respectively (P=0·51). The median durations of anaesthesia (interquartile range) for cases and controls were 72·5 (45 to 235) minutes and 80 (50 to 140) minutes, respectively (P=0·14). At the univariable level, patients with a high-risk status (ASA grade 3 to 5) had a significantly increased odds of death compared with patients at low risk (ASA 1 to 2) (Table 1). Patients receiving acepromazine as part of the premedication were at reduced odds of death relating to anaesthesia, compared with not receiving acepromazine and compared with other premedicants. In the latter comparison, two cases that had received no premedication were Variable Category β se β OR 95% CI P

Implications of genetic traits on vaccine efficacy.

Literature on genetic screening in the community suggests that people having specific genotypes may either get or protect from infection, for example, malaria, human papilloma virus, and haemophilic influenza, for which vaccines are either already developed or being targeted. In such a situation, the evaluation of the efficacy of vaccine in the community needs to be examined with caution. In this paper, I present a method for the estimation of vaccine efficacy (VE) in the presence of genetic traits/component (theta) and the sample size required to estimate the 95 per cent CI with a given relative width for the estimated vaccine efficacy. Considering true efficacy ranging from 40 to 80 per cent and the possible values of the genetic component (theta) ranging from 0 to 60 per cent, the VE was estimated. The 95 per cent confidence intervals (CI) for the estimated VE for relative widths (R) 1.0 and 0.1 were computed. The sample sizes required for each of the unvaccinated and vaccinated cohorts were computed for estimating the 95 per cent CI for given incidence rates in the unvaccinated (Iu) cohort. In the presence of genetic traits I found that the VE was consistently overestimated. There existed change in the location as well as the asymmetry of the 95 per cent CIs over the point estimate of VE. The sample size required for estimating 95 per cent CI of VE was substantially reduced, resulting in savings. The more the genetic component (theta) affecting disease in the community, the more the savings in sample size. I examined the above estimators for (i) VE, (ii) 95 per cent CI for VE and (iii) sample size required for estimating 95 per cent CI of VE using the real-life data from the Haemophilus influenzae type b vaccine trial conducted in Finland and the global genetic structure of encapsulated H. influenza. Because of escalated VE and large savings in sample size for estimating the 95 per cent CI for VE, I recommend that the design should consider the genetic component that causes/protects from infection/disease for the evaluation of efficacy of vaccine in the field.

Psychotropic medication use and risk of hormone-related cancers: the New York University Women's Health Study.

The use of psychotropic medications may increase the risk of hormone-related cancers in females through increased gonadotropin secretion, but the data from epidemiologic studies are limited to evaluate the hypothesis. The association between the use of psychotropic medications and cancer incidence was studied in a prospective cohort study that involves 15,270 women who participated in mammographic screening. The relative risks (RR) and 95 per cent confidence intervals (CIs) for cancer associated with the use of psychotropic medications were estimated by the Cox's proportional hazard model. During an average of 7.3 years of follow-up, 1,130 incident cases of cancer were identified, including 566 breast, 67 endometrial and 47 ovarian cancers. The use of any type of psychotropic medication at baseline was associated with increased risks of breast [relative risk (RR) = 1.39, 95 per cent CI 1.11-1.74], endometrial (RR=1.71; 95 per cent CI 0.93-3.14) and ovarian (RR= 1.48, 95 per cent CI 0.69-3.16) cancers, whereas no increase in risk was observed for other cancers (RR = 1.06). When the subjects were divided by menopausal status at baseline, premenopausal women tended to have higher risk of all hormone-related cancers (RR = 1.73, 95 per cent CI 1.27-2.35) than postmenopausal women (RR=1.23, 95 per cent CI 0.94-1.62). The magnitude of the RR associated with the use of these medications did not change by length of follow-up. Analysis by type of medication did not find that the association was limited to specific types. The observed association needs to be confirmed in further studies based on more detailed medication history.

Management of ischaemic heart disease in primary care: towards better practice. STaRNet. South Thames Region Network.

Ischaemic heart disease is the commonest cause of mortality in the United Kingdom. The objective of this study was to assess the management of patients with ischaemic heart disease in primary care, focusing particularly on the management of hypercholesterolaemia. A cross-sectional survey was carried out of the clinical records of patients aged 25-74 years with confirmed ischaemic heart disease in six general practices (total list size 56 600). Recording of risk factors varied from 97 per cent for blood pressure to 73 per cent for cholesterol measurement. Seventy-two per cent of the patients had adequate blood pressure control, based on their last recorded blood pressure. Sixty-one per cent (267) were known to be taking aspirin daily and 29 per cent (125) had undergone revascularization treatment. Sixty-eight per cent (296) of the patients had pre-treatment cholesterol levels of 5.5 mmol/l or greater and 34 per cent (147) were currently taking lipid lowering drugs. Statins were the most commonly used cholesterol lowering agents and were being taken by 30 per cent (131) of the patients. Patients who had undergone revascularization treatment had levels of recording of risk factors similar to other patients with ischaemic heart disease but were more likely to be taking daily aspirin (71 per cent versus 57 per cent, relative risk 1.24, 95 per cent confidence intervals (CI) 1.07-1.44). The mean pre-treatment cholesterol was 6.49mmol/l and the mean post-treatment cholesterol 5.80 mmol/l (difference 0.69 mmol/l, 95 per cent CI 0.55-0.84 mmol/l). Systematic searches of computerized and paper medical records can identify subgroups of patients who will benefit from continuing follow-up in primary care. The results of this study suggest that ischaemic heart disease remains an area where there is scope to improve the management of patients in primary care. Considerable effort will be required from the members of the primary health care team to achieve this objective, particularly in the areas of computerized data collection and in the identification and recall of patients.

FETAL DEATH AFTER EXPOSURE TO METHYLENE BLUE DYE DURING MID-TRIMESTER AMNIOCENTESIS IN TWIN PREGNANCY

Methylene blue dye use during mid-trimester amniocentesis in twin pregnancy is associated with a high risk of small intestinal atresia. It is plausible that the effects of methylene blue as a fetotoxic agent may also lead to fetal death. We conducted a retrospective cohort study of all women who had an amniocentesis during twin pregnancy from 1980 through 1991 in New South Wales, Australia. Women who were exposed to methylene blue dye during the procedure were compared with women who had amniocentesis without dye exposure. Fetal death occurred in 31.8 per cent of pregnancies that had exposure to a high concentration of methylene blue, compared with 14.5 per cent of pregnancies exposed to a low concentration and 4.3 per cent of pregnancies with no exposure to dye. The unadjusted and adjusted risks and 95 per cent confidence intervals (CIs) for fetal death after any exposure to dye were 5.03 (2.12-11.91) and 8.52 (2.28-31.80), respectively. The adjusted odds ratio and 95 per cent CIs for the low and high concentration dye solutions were 4.63 (0.93-23.13) and 14.98 (3.40-66.08), respectively (chi-squared test for trend P < 0.001). Fetus papyraceous was significantly more likely among pregnancies exposed to a high concentration of methylene blue (P < 0.001) than among unexposed pregnancies. These results support the hypothesis that methylene blue dye use during mid-trimester amniocentesis in twin pregnancy increases the risk of fetal death.