Methodologic rigor of clinical trials on surgical management of eyes with coexisting cataract and glaucoma.

OBJECTIVE:

To assess the methodologic quality of published studies of the surgical management of coexisting cataract and glaucoma.

DESIGN:

Literature review and analysis.

METHOD:

We performed a systematic search of the literature to identify all English language articles pertaining to the surgical management of coexisting cataract and glaucoma in adults. Quality assessment was performed on all randomized controlled trials, nonrandomized controlled trials, and cohort studies. Overall quality scores and scores for individual methodologic domains were based on the evaluations of two experienced investigators who independently reviewed articles using an objective quality assessment form.

MAIN OUTCOME MEASURES:

Quality in each of five domains (representativeness, bias and confounding, intervention description, outcomes and follow-up, and statistical quality and interpretation) measured as the percentage of methodologic criteria met by each study.

RESULTS:

Thirty-six randomized controlled trials and 45 other studies were evaluated. The mean quality score for the randomized, controlled clinical trials was 63% (range, 11%-88%), and for the other studies the score was 45% (range, 3%-83%). The mean domain scores were 65% for description of therapy (range, 0%-100%), 62% for statistical analysis (range, 0%-100%), 58% for representativeness (range, 0%-94%), 49% for outcomes assessment (range, 0%-83%), and 30% for bias and confounding (range, 0%-83%). Twenty-five of the studies (31%) received a score of 0% in the bias and confounding domain for not randomizing patients, not masking the observers to treatment group, and not having equivalent groups at baseline.

CONCLUSIONS:

Greater methodologic rigor and more detailed reporting of study results, particularly in the area of bias and confounding, could improve the quality of published clinical studies assessing the surgical management of coexisting cataract and glaucoma.

Ultra-high-resolution Observations of MHD Waves in Photospheric Magnetic Structures

Here we review the recent progress made in the detection, examination, characterisation and interpretation of oscillations manifesting in small-scale magnetic elements in the solar photosphere. This region of the Sun's atmosphere is especially dynamic, and importantly, permeated with an abundance of magnetic field concentrations. Such magnetic features can span diameters of hundreds to many tens of thousands of km, and are thus commonly referred to as the `building blocks' of the magnetic solar atmosphere. However, it is the smallest magnetic elements that have risen to the forefront of solar physics research in recent years. Structures, which include magnetic bright points, are often at the diffraction limit of even the largest of solar telescopes. Importantly, it is the improvements in facilities, instrumentation, imaging techniques and processing algorithms during recent years that have allowed researchers to examine the motions, dynamics and evolution of such features on the smallest spatial and temporal scales to date. It is clear that while these structures may demonstrate significant magnetic field strengths, their small sizes make them prone to the buffeting supplied by the ubiquitous surrounding convective plasma motions. Here, it is believed that magnetohydrodynamic waves can be induced, which propagate along the field lines, carrying energy upwards to the outermost extremities of the solar corona. Such wave phenomena can exist in a variety of guises, including fast and slow magneto-acoustic modes, in addition to Alfven waves. Coupled with rapid advancements in magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly investigate how wave motion is generated in the solar photosphere, which oscillatory modes are most prevalent, and the role that these waves play in supplying energy to various layers of the solar atmosphere.