J. Gail Neely

A PRACTICAL GUIDE TO UNDERSTANDING KAPLAN-MEIER CURVES

In 1958, Edward L. Kaplan and Paul Meier collaborated to publish a seminal paper on how to deal with incomplete observations. Subsequently, the Kaplan-Meier curves and estimates of survival data have become a familiar way of dealing with differing survival times (times-to-event), especially when not all the subjects continue in the study. “Survival” times need not relate to actual survival with death being the event; the “event” may be any event of interest. Kaplan-Meier analyses are also used in nonmedical disciplines. The purpose of this article is to explain how Kaplan-Meier curves are generated and analyzed. Throughout this article, we will discuss Kaplan-Meier estimates in the context of “survival” before the event of interest. Two small groups of hypothetical data are used as examples in order for the reader to clearly see how the process works. These examples also illustrate the crucially important point that comparative analysis depends upon the whole curve and not upon isolated points.

Tutorials in Clinical Research: Part IV: Recognizing and Controlling Bias

Objective This is the fourth of a series of Tutorials in Clinical Research. 1–3 The objectives of this article are to heighten reader awareness of biases and of methods to reduce their impact and to provide an easy reference document for the reader during future journal reading.

Otologics middle ear transducer™ ossicular stimulator: Performance results with varying degrees of sensorineural hearing loss

Objectives This study was conducted to demonstrate the safety and efficacy of the Otologics Middle Ear Transducer™ (MET™) Ossicular Stimulator and, in particular, to compare the audiologic benefits of this novel form of electromechanical stimulation with those of conventional acoustical amplification. Material and Methods A total of 282 patients were implanted with the device in Europe and the USA. Pure-tone audiometry, speech recognition and subjective assessment of benefit were tested before the surgery and 2, 3, 6 and 12 months afterwards. The US patients were fitted with a digital hearing aid for a minimum of 4 weeks prior to surgery, and the same benefit measures were performed with the digital hearing aid and their “walk-in” hearing aid. Results Group mean postoperative bone and air conduction thresholds did not change significantly from preoperative levels. Postoperative air conduction thresholds decreased slightly in some individual patients, due to the mass loading effect exerted by the transducer on the ossicles. Sufficient gain was available to reach target prescription levels for moderate to severely impaired hearing individuals. Speech and subjective assessment of patient preference indicated that patients did as well or better with the MET Ossicular Stimulator than with their “walk-in” aid or the standardized digital aid. Conclusion The capability of the MET Ossicular Stimulator to provide appropriate gain as a function of degree of hearing loss indicates that the device is a viable treatment for moderate to severe sensorineural hearing loss in adults.

Patterns of Facial Nerve Synkinesis

Facial nerve synkinesis is an extremely distressing sequela of facial paralysis, and its prevention and treatment are less than adequate. Improved therapeutic interventions await better understanding of its pathogenesis.

Nucleus Freedom North American clinical trial

OBJECTIVE: To evaluate hearing outcomes and effects of stimulation rate on performance with the Nucleus Freedom cochlear implant (Cochlear Americas, Denver, CO). STUDY DESIGN AND SETTING: Randomized, controlled, prospective, single-blind clinical study using single-subject repeated measures (A-B-A-B) design at 14 academic centers in the United States and Canada and comparison with outcomes of a prior device by the same manufacturer. PATIENTS: Seventy-one severely/profoundly hearing impaired adults. RESULTS: Seventy-one adult recipients were randomly programmed in two different sets of rate: ACE or higher rate ACE RE. Mean scores for Consonant Nucleus Consonant words is 57%, Hearing in Noise Test (HINT) sentences in quiet 78%, and HINT sentences in noise 64%. Sixty-seven percent of subjects preferred slower rates of stimulation, and performance did not improve with higher rates of stimulation using this device. CONCLUSIONS: Subjects performed well, and there was no advantage to higher stimulation rates with this device. SIGNIFICANCE: Higher stimulation rates do not necessarily result in improved performance.

Quantitative Assessment of the Variation Within Grades of Facial Paralysis

A completely objective, unambiguous outcome measure of facial function is now available. A new automated computer‐assisted clinimetric system combines the crucial detection capabilities of the human observer and the unique capacity of the computer to quantify the image light reflectance difference observed during facial expression.

Sunnybrook facial grading system: Reliability and criteria for grading†

In clinical research, which is distinctly quantitative and rigidly fixed to a written protocol, the need for precision is great, especially when multicenter trials are planned. The Sunnybrook Facial Grading System (SB) is a well‐established tool for assessing facial movement outcomes; however, some ambiguities do arise. The purpose of this study was to construct specific grading criteria and to test the intra‐rater and inter‐rater reliability before and after the use of these criteria. The hypothesis was that even in naïve observers, specific criteria improve reliability.

Tutorials in clinical research, Part VIII: Creating a Journal club

Objective The present report is the eighth in a series of sequential tutorials entitled “Tutorials in Clinical Research.” The objective of the report is to provide the reader with information to create or refine a journal club.

Validation of Objective Measures for Facial Paralysis

A shift from subjective scales to objective measures of facial paralysis requires physical models against which to validate and calibrate the new objective techniques. The purpose of this report was to demonstrate such a model and to test the capacity of an objective computer system to accurately measure physical change. The physical model consisted of an advancing edge of a spreading gelatin film. The model was measured in submillimeter increments. Concurrent measurements were made using the computed system. Ten trials were conducted. The objective system proved to be exquisitely sensitive (0.03 mm) and highly correlated with the physical criterion model (Pearsons product moment correlation coefficient [r]=0.9849). Sensitive and calibrated objective methods of analysis of facial motion are crucial to the design of clinical trials, clinical studies of nerve regeneration, and comparisons of reanimation techniques.

A practical guide to understanding systematic reviews and meta-analyses

A systematic review is a transparent and unbiased review of available information. The published systematic review must report the details of the conduct of the review as one might report the details of a primary research project. A meta-analysis is a powerful and rigorous statistical approach to synthesize data from multiple studies, preferably obtained from a systematic review, in order to enlarge the sample size from smaller studies to test the original hypothesis and/or to generate new ones. The objective of this article is to serve as an easy to read practical guide to understand systematic reviews and meta-analyses for those reading them and for those who might plan to prepare them.