Statistical significance, clinical importance and effect sizes: Enhancing understanding of a study's results.

Background: The proper interpretation of a study's results requires both excellent understanding of good methodological practices and deep knowledge of prior results, aided by the availability of effect sizes.

Methods: This review takes the form of an expository essay exploring the complex and nuanced relationships among statistical significance, clinical importance, and effect sizes.

Results: Careful attention to study design and methodology will increase the likelihood of obtaining statistical significance and may enhance the ability of investigators/readers to accurately interpret results.

The Sinhala version of the pain catastrophizing scale: validation and establishment of the factor structure in pain patients and healthy adults.

Objective: This study was conducted to translate the Pain Catastrophizing Scale into and adapt it to the Sinhala language and to examine its psychometric properties and factor structure in pain patients and healthy adults in Sri Lanka.

Setting And Design: A cross-sectional study was conducted, recruiting pain patients from multiple clinics and healthy adults from the community as convenience samples.

Methods: Cross-cultural adaptation of the Pain Catastrophizing Scale for Sinhala speakers was carried out using recommended methods.

Ocular problems in low-income and minority children.

Purpose: To report the prevalence rates of screen failures for uncorrected refractive error, abnormal or excessive levels of hyperopia, problems in binocular vision, and deficiency of near point acuity as related to age and ethnicity in children.

Methods: Vision screening tests were administered to 9,743 African-American, Hispanic, and white children aged 6 to 11 years in the Kansas City (United States) metropolitan area. Screening was performed by health professions students using HOTV charts for refractive errors, hyperopia, and near point acuity and a Random Dot E test for binocular vision.

Headache and oral parafunctional behaviors.

This study tested the hypotheses that individuals with headaches would show significantly more oral parafunctional behaviors than non-headache controls, be diagnosed with one or more temporomandibular disorders (TMD) significantly more frequently than controls, and would report significantly less pain and other symptoms of headache after participating in a habit reversal treatment to reduce oral parafunctional behaviors, compared to a wait list control. In Phase I, individuals with and without self-reported headaches were examined by a blinded examiner and participated in a week-long experience sampling protocol (ESM) to assess oral parafunctional behaviors, pain, and emotional states. In Phase II, those with headaches were randomly assigned to either a habit reversal treatment or to a wait list control group.

Exercise during pregnancy: the role of obstetric providers.

Context: Obstetric providers are logical choices for conveying information about physical activity to their pregnant patients. However, research regarding obstetric providers counseling pregnant patients about physical activity is sparse.

Objectives: To investigate the association between obstetric providers discussing exercise with their pregnant patients and patients' exercise behaviors and to explore factors related to obstetric providers discussing exercise and other health behaviors (tobacco use, alcohol use, and nutrition) with their patients.

Autonomic dysregulation in headache patients.

To analyze autonomic nervous system activity in headache subjects, measurements of heart rate variability (HRV), skin temperature, skin conductance, and respiration were compared to a matched control group. HRV data were recorded in time and frequency domains. Subjects also completed self-report questionnaires assessing psychological distress, fatigue, and sleep dysfunction.

Establishing the content validity of palpatory examination for the assessment of the lumbar spine using ultrasonography: a pilot study.

Context: Practitioners of manipulative medicine have long sought to prove the intra- and interexaminer reliability of palpatory examinations in assessing somatic dysfunction. However, decades of research have yet to achieve the level of reproducibility needed to satisfy evidence-based criteria.

Objectives: To examine the content validity of segmental motion evaluations using ultrasonographic measurements and to investigate the implication of these results for understanding the effects of an osteopathic manipulative treatment technique--high-velocity, low-amplitude (HVLA)--applied to somatic dysfunction in the lumbar spine.

Tooth contact versus clenching: oral parafunctions and facial pain.

Aims: To test the hypothesis that estimates of time spent in tooth contact are significantly greater than estimates of time spent clenching, and to test the hypothesis that tooth contact is greater in pain patients, particularly those reporting facial or head pain, than those with pain elsewhere in the body.

Methods: An anonymous, voluntary, confidential questionnaire was administered to 235 patients seeking care at a general medical clinic. The questionnaire assessed demographic variables, presence and location of pain, and percentage of time spent in tooth contact and in clenching.

Anatomic changes related to laryngeal descent from birth to 1 year of age: do they play a role in SIDS?

We conducted a retrospective study to measure laryngeal descent in human infants and to determine if there is any correlation between the associated anatomic changes and the timing of the peak incidence of sudden infant death syndrome (SIDS), which is 2 to 4 months of age. We performed a computerized search of hospital records at our institution to identify magnetic resonance imaging (MRI) scans of the head and neck and plain radiographs of the lateral neck in patients younger than 1 year of age (range: 1 to 357 days). After unusable images were excluded, 79 head and neck MRI scans and 111 lateral neck x-rays were suitable for study.

Pharmacokinetics of concurrent administration of fosamprenavir and atazanavir without ritonavir in human immunodeficiency virus-negative subjects.

Study Objective: To quantify the pharmacokinetics of amprenavir and atazanavir (administered as the prodrug fosamprenavir) alone and in combination in human immunodeficiency virus (HIV)-negative subjects.

Design: Randomized, open-label, three-way crossover study.

Setting: Research facility.

Short-term hematologic and hemodynamic effects of osteopathic lymphatic techniques: a pilot crossover trial.

Context: Research into the physiologic effects of osteopathic lymphatic techniques has been somewhat limited.

Objective: To assess the short-term hematologic and hemodynamic effects of a comprehensive lymphatic treatment protocol.

Methods: Randomized crossover design that included 10-minute lymphatic treatment and rest (control) protocols delivered 1 week apart for a small pilot group of healthy men (N=15).

"One pill, once daily": what clinicians need to know about Atriplatrade mark.

As the number of persons chronically prescribed antiretrovirals has grown and the realization that antiretrovirals are required to be continued for life, pharmaceutical manufacturers have developed new classes of agents, improved the pharmacokinetics of marketed products through dosing reformulations, and in an effort to maximize success with respect to adherence, compiled into a single dosing unit all necessary elements for an antiretroviral regimen. Atriplatrade mark represents the first ever fixed-dose combination antiretroviral available. This article reviews currently available data on this agent, the impact of resistance on clinical use and implementation, as well as extensive descriptions of the pharmacokinetics, adverse effects and drug-interactions warranting consideration.

Temporomandibular disorders and facial pain: a psychophysiological perspective.

This article presents a psychophysiological perspective on temporomandibular muscle and joint disorders (TMJD) and facial pain. After a brief introduction to TMJD, the article presents data, largely derived from work carried out in my laboratory, that address four questions: (1) What are the consequences of parafunctional activities? (2) Do TMJD patients engage in parafunctional activities? (3) Why are TMJD patients unaware of these activities? and (4) What are the implications of these findings for treatment? The findings suggest that low-level parafunctions increase pain in otherwise pain-free individuals and can produce symptoms sufficiently severe to meet the diagnostic criteria for TMJD diagnoses of myofascial pain and/or arthralgia. Patients with certain forms of TMJD report very high levels of parafunctional tooth contact.

Diurnal variation in pain reports in temporomandibular disorder patients and control subjects.

Aims: To test the hypothesis that temporomandibular disorder (TMD) patients have characteristic diurnal patterns of pain that are associated with diurnal or nocturnal parafunctions.

Methods: Experience sampling methods were used to obtain information on pain from subjects (n = 84) diagnosed, according to the Research Diagnostic Criteria for TMD, with myofascial pain, myofascial pain and arthralgia, disc displacement, and from non-TMD controls. Variations in pain as reported on the pager questionnaire form were modeled as linear, exponential, and quadratic effects.

Comparison of habit reversal and a behaviorally-modified dental treatment for temporomandibular disorders: a pilot investigation.

This study tested the hypothesis that a habit reversal program emphasizing awareness and reduction of masticatory muscle activity would significantly reduce pain in patients diagnosed with chronic temporomandibular disorder (TMD) and would be a competitive alternative to a behaviorally-modified dental intervention. Eight individuals diagnosed with TMD were randomly assigned to a splint therapy or habit reversal group. Patients in the splint group received an interocclusal appliance (splint) fabricated from acrylic and were instructed to wear the splint day and night up to a maximum of 20 h per day.

Properties of silorane-based dental resins and composites containing a stress-reducing monomer.

Objective: To evaluate properties of silorane-based resins and composites containing a stress reducing monomer.

Methods: Resin mixtures and composites were formulated containing (a) a developmental stress reducing monomer [TOSU; Midwest Research Institute]; (b) Sil-Mix (3M-ESPE); (c) photo cationic initiator system. Standard BISGMA/TEGDMA resin (B/T) and composite (Filtek Z250) were used as controls.

Psychophysiological definitions of clenching.

This study tested the hypothesis that individuals show considerable variability in EMG activity produced by the masticatory muscles when they are instructed to clench than when they are instructed to make minimal or maximal contact. Twenty individuals without temporomandibular disorder (TMD) pain participated in a biofeedback-training task to establish a relaxed baseline. They were instructed to clench their teeth according to their personal definition of the term, while EMG data were collected.

A comparison between two types of radiographic film for accuracy of measurements of approximal osseous defects.

Aim: The purpose of this study was to compare two types of conventional radiographic film: Ekta-speed plus and Insight (Eastman Kodak Co, Rochester NY, USA) for accuracy of measurements of approximal bone loss.

Methods And Materials: Four dried human mandibles with complete dentition were selected. Radiographic images were made with a standardized technique.

Perceived efficacy, indications, and information sources for medically indigent patients and their healthcare providers regarding dietary supplements.

Background: Evidence exists that medically indigent and minority patients use dietary supplements at rates as high or higher than that of the general population. Safety concerns regarding the use of dietary supplements are further exacerbated by a suboptimal level of patient disclosure and provider inquiry.

Objective: To determine dietary supplement use, indications, perceived efficacy, and information sources of patients and providers using a pilot study in a clinic for the medically indigent.

Efficacy of biofeedback-based treatments for temporomandibular disorders.

Bibliographic searches identified 14 controlled and uncontrolled outcome evaluations of biofeedback-based treatments for temporomandibular disorders published since 1978. This literature includes two randomized controlled trials (RCTs) of each of three types of biofeedback treatment: (1) surface electromyographic (SEMG) training of the masticatory muscles, (2) SEMG training combined with adjunctive cognitive-behavioral therapy (CBT) techniques, and (3) biofeedback-assisted relaxation training (BART). A detailed review of these six RCTs, supplemented with information from non-RCT findings, was conducted to determine the extent to which each type of intervention met treatment efficacy criteria promulgated by the Association for Applied Psychophysiology and Biofeedback (AAPB).

Alexithymia and pain in temporomandibular disorder.

Objective: To clarify the relationship of global alexithymia and its facets with pain, assessed prospectively using experience sampling methods (ESMs), in temporomandibular disorder (TMD).

Methods: People with painful TMD (n=49), pain-free somatic controls (24 people with disk displacement), and healthy controls (n = 28) completed measures of alexithymia (Toronto Alexithymia Scale-20 [TAS-20]) and depressed mood. Patients with painful TMD used ESM to record jaw pain multiple times daily for a week.

Tooth contact in patients with temporomandibular disorders.

Both experimental and retrospective studies suggest a link between parafunctions and pain in temporomandibular disorder (TMD) patients. To investigate the role of parafunctions in TMD, experience sampling methodology was used as a prospective test of the hypothesis that patients with TMD have higher levels of tooth contact and tension than non-TMD controls. Three groups of TMD patients and a group of normal controls carried pagers for one week, were contacted approximately every two hours by an automated calling system, and completed questionnaires assessing tooth contact, tension, and pain at each contact.