Macular Degeneration- The Highs and Lows
– Sunday, 30 March 2014, 7:04 PM
Level 4 (low level)
T. Cleary, “Aggressive wet age-related macular degeneration”, Illuminate 1 10 (2010) 26-31
This is a case report which describes a single patient’s clinical findings and the subsequent course of action that took place. The author has included background information regarding macular degeneration however sources ranged between level 3 and level 4.Sources included distribution company websites which could be bias and unreliable as well as other case reports. In addition references dated from 1971 with only a few dating in 2009. Having the case report published in 2010; one would anticipate more up to date references.The strength of the evidence was weak and the size of the effect reflects one patient which may or may not be applicable to the general wet MD population.
For the reasons outlined above, I do not consider this evidence to be reliable, but rather a case example to note regarding one individual. Having said that, the discussion served as a good platform to raise awareness regarding various and alternate treatment and management of wet MD.
Level 1 (high level)
Chakravarthy U, Wong TY, Fletcher A, Piault E, Evans C, Zlateva G, et al. Clinical risk factors for age-related macular degeneration: a systematic review and meta-analysis. BMC ophthalmology. 2010;10:31
This is a systematic review which collated and critically analyzed, appraised and synthesized several high level 2studies ( double blinded/randomized control) regarding clinical risk factors for ARMD , also used meta-analysis to synthesize data and results from many papers into a single quantitative summary. This gives strength to the evidence due to quality. This rigorous process that is implemented in analyzing the collection of studies minimizes bias misinformation. The review also utilized 18 prospective and cross-sectional studies and 6 case control studies involving 113,780 persons with 17,236 cases of late AMD, adding strength to the evidence due to size, allowing for trends and generalizations to be established. The topic in question was regarding age related macular degeneration and its associated clinical risk factors. The studies reviewed were conducted on humans and looked at various precursors that could be a clinical risk factors for MD; making it clinically relevant and allowing it to form the basis for future clinical decisions. For these reasons, I consider this evidence to be reliable.
– Monday, 31 March 2014, 2:06 PM
Previously I had gave an example of how I faced with amblyopia patient. So,this time I will gives an examples of high and low quality of evidence in amblyopia treatment:
1. High level quality of study : A randomised trial of increasing patching for amblyopia, Ophthalmology,November 2013, Volume 120, Issue 11,Pages 2270-2277 by Pediatric Eye Disease Investigator Group. The reason why I choose this study as high quality of evidence because of few factors such as :
– This study use level I study design which is prospective,randomised and multicenter clinical trial and have comparison between treatment and control group
– The statistical findings was reliable with 90% power with type I error rate with no more than 5% loss to follow up and can reject null hypothesis.
– No element of bias because author was not sponsored by any company and do not have any commercial interest in this study
– Currency : This study was published in 2013 and was updated and have improvement in the same previous study conducted by Pediatriac Eye Disease Investigator Group(PEDIG).
2. Low quality of evidence : Defining and measuring treatment outcome in unilateral amblyopia, Br J Ophthalmol, Oct 2003; 87(10): 1229-1231 by CE Stewart, MJ Moseley and AR Fielder.
I am consider this study as low level of quality because of the study method use the level IV,which are literature appraisal and descriptive case presentation. This method is a weak method to use as high strength of evidence. This study also do not have control group to measure the treatment outcome.