The study:
A home-based, nurse-delivered exercise programme reduced falls and serious injuries in people ³ 80 years of age. Robertson et al.
Effectiveness and economic evaluation of a nurse delivered home exercise
programme to prevent falls. 1: randomised controlled trial. [1]
appeared in both Evidence-Based Medicine [2] and in Evidence-Based Nursing.[3]...
The study:
A home-based, nurse-delivered exercise programme reduced falls and serious injuries in people ³ 80 years of age. Robertson et al.
Effectiveness and economic evaluation of a nurse delivered home exercise
programme to prevent falls. 1: randomised controlled trial. [1]
appeared in both Evidence-Based Medicine [2] and in Evidence-Based Nursing.[3]
The commentators differ in their perceptions of this paper. Edwards states that "Study results are promising and suggest that nurses have an important role to play in the
promotion of appropriate exercise that targets fall prevention among seniors."
Whereas Robbins believes "We can be less sure from this study what the actual "treatment" needs to be and who should provide it."
For me several issues are raised:
·Is it necessary to replicate
summaries of studies in both
journals, it seems wasteful of
resources
·What about the possibility of
joint (multidisciplinary)
commentaries
·The eLetters section where issues
such as those I have raised could
be aired still contains no letters
John Platt
References
(1) A home-based, nurse-delivered exercise programme reduced falls and serious injuries in people ³ 80 years of age Robertson MC, Devlin N, Gardner MM, et al.
Effectiveness and economic evaluation of a nurse delivered home exercise
programme to prevent falls. 1: randomised controlled trial.BMJ 2001 Mar 24;322:697-701.
(2) Robbins JA, Robertson MC, Campbell AJ (commentator). A home-based, nurse-delivered exercise programme reduced falls and serious injuries in people ³ 80
years of age. Evid Based Med 2001;6:182.
(3) Edwards N. A home based, nurse delivered exercise programme reduced falls and serious injuries in people 80
years of age. Evid Based Nurs 2002;5:22.
It is well documented that Free radicals (FRs) and their Oxidative Reactions are implicated in more than 70 diseases and disorders [1,2], including inflammatory reactions, such as alergies and rheumatoid arthritis. As FRs and Oxidative stress are also implicated in many cell death processes [3], many scientific activities are being done to discover possible protective effects of the antioxidant therapy [1]. Today...
It is well documented that Free radicals (FRs) and their Oxidative Reactions are implicated in more than 70 diseases and disorders [1,2], including inflammatory reactions, such as alergies and rheumatoid arthritis. As FRs and Oxidative stress are also implicated in many cell death processes [3], many scientific activities are being done to discover possible protective effects of the antioxidant therapy [1]. Today, based on Oriental and Mediterranean dietetic studies, we know that many foods,the functionals or nutraceuticals, can improve physiological properties of the human body, improving health and preventing diseases. I should be emphazised that antioxidant activity of foods is one of the most important functional food atributtes.
Persenone A, an avocado compound, was able to inhibit two peroxidative enzymes involved in inflammatory responses, the nitric oxide synthase and cyclooxygenase in mouse macrophages [4]. Murcia et al. [5] demonstrated that avocado possess antioxidant activities as well as many other Mediterranean and Tropical Fruits do. Some years ago, Kikusaki and Nakatani [6] had observed that 12 Ginger compounds have antioxidant activity.
This year, Kim et al. [7] reported that ginger, avocado, carrot, turnip and shimeji mushrooms had higher superoxide radical scavenging activity,
suggesting that this phytochemicals can prevent oxidative DNA damage, the first step in cancer carcinogenesis.
It should be noted that in rheumatoid arthritis, there are intensive production of FRs and the antioxidant therapy is very important to control the damaging effects of these substances. As exposed before, Ginger, Avocado and other foods are rich sources of antioxidants with a great potential to be explored in rheumatoid arthritis. However, many more basic and studies are necessary to support a teraphy.
References
(1) Ferrari CKB (1998). Lipid peroxidation in foods and biological systems: General mechanisms and Nutritional and Pathological implications. Rev. Nutr., 11: 3-14 (in portuguese).
(2) Ferrari CKB (2001). Oxidative Stress Pathophysiology: Searching for an Effective Antioxidant Protection. Int. Med. J., 8: 175-84.
(3) Ferrari CKB (2000). Free Radicals, lipid peroxidation and antioxidants: Implications for cancer, cardiovascular, and neurological diseases. Biologia, 55: 581-90.
(4) Kim OK, Murakami A, Takahashi D, Nakamura Y,Torikai K, Kim HW, Ohigashi H (2000). An avocado constituent, persenone A, suppresses expression of inducible forms of nitric oxide synthase and cyclooxygenase in macrophages, and hydrogen peroxide generation in mouse skin. Biosci. Biotechnol. Biochem., 64: 2504-7.
(5) Murcia MA, Jimenez AM, Martinez-Tomé M (2001). Evaluation of the antioxidant properties of Mediterranean and tropical fruits compared with common food additives. J. Food Protect., 64: 2037-46.
(6) Kikusaki H, Nakatani N (1993). Antioxidant effect of some Ginger constituents. J. Food Sci., 58: 1407-10.
(7) Kim HW, Murakami A, Nakamura Y, Ohigashi H (2002). Screening of edible Japanese plants for suppressive effects on phorbol ester-induced superoxide generation in differentiated HL-60 cells and AS52 cells. Canc. Let., 176:7-16.
Dr Parienti and colleagues have raised concerns [1] about a section of the commentary for which I am responsible. Their letter highlights the lack of a standard typology for trial design in clinical epidemiology. At the heart of this issue is not only what to call the different types of clinical trial, but how to analyse the results of each trial. Was the trial by Dr Parienti and colleagues a cluster randomi...
Dr Parienti and colleagues have raised concerns [1] about a section of the commentary for which I am responsible. Their letter highlights the lack of a standard typology for trial design in clinical epidemiology. At the heart of this issue is not only what to call the different types of clinical trial, but how to analyse the results of each trial. Was the trial by Dr Parienti and colleagues a cluster randomised controlled trial (RCT) as I described it? In the trial each service (or study centre) was randomised to an alternating sequence, commencing with either the alcohol handrub first, or handscrubbing first. The trial could have been described as a cross-over design, although in cross-over designs, it is usually an individual that is randomised to an order of treatment.[2] Where the unit of randomisation is an intact social unit, such as a community, family, or service, the trial is usually called a cluster RCT.[3] Dr Parienti quite rightly points out that in cluster RCTs the study centre is normally randomised to the treatment or control, whereas he and his colleagues randomised each service to a sequence of interventions. Therefore, perhaps the trial is most accurately described as a cluster cross-over RCT.
The substantive issue in Dr Parienti's letter is how their trial should have been analysed. It is my view that the trial should have been analysed as though it were a cluster design, as services were randomised to a sequence of interventions. Cluster designs can balance out the impact of extraneous variables, but less efficiently than trials that randomise by individual. Cluster designs normally adjust for this by inflating the number of clusters and participants that need to be enrolled in the trial.[4] Dr Parienti and colleagues do not seem to have done this, and there were only six services (or clusters) in their study. As Dr Parienti states, each service would have acted as its own control, and the 15 sequential cross-over periods certainly adds to the study's validity. I was perhaps remiss in not pointing this out in the commentary.
Even though the cross-over periods controlled for between-cluster variance, the investigators did not analyse for the impact of time periods. Each service has a flow of patients and staff through it that will vary in some way - for instance there will be seasonal variation, which even if small, could influence the outcome. Therefore the services will not be the same over time. If the patients or the cross-over periods had been randomised, then the possible influence of this effect would have been balanced out. Randomising the service to an sequence of intervention would not have been able to control for this effect; and thus the trial's standard error could actually be greater, confidence intervals wider, and the p values larger than the reported result.[5] If a multi-level analysis (patient, time period and service) had been conducted then the reader could be reasonably assured of the lack of difference between the interventions. It is possible that even had Dr Parienti and colleagues used this method of analysis, they would have found little difference from the result they published. However, Dr Parienti and colleagues did not follow the dictum "as you randomise, so you shall analyse" and the knowledgeable reader is left uncertain as to whether handrubbing with alcohol as compared with handscrubbing is as equivalent as the study reports.
Acknowledgement
I am grateful to Dr David Torgerson, University of York, and Mark Jones, University of Auckland, for their helpful review.
References
(1) Jean-Jacques Parienti, for the ACM study group. Only cluster design lead to cluster effect [electronic response to Moralejo D and Jull D Handrubbing with an aqueous alcohol solution was as effective as handscrubbing with antiseptic soap for preventing surgical site infections] evidencebasednursing.com 2003 http://ebn.bmjjournals.com/cgi/eletters/6/2/55#12
On behalf our Study group, I would like to thank EBN’s Editors for
their interest in our work.
In their review, major concerns regarding the
design and analysis of our study were raised by Drs Moralejo and Jull,
mainly because antiseptic protocols were randomised by services (called "clusters") but outcome was analysed by patients. The authors concluded
that while our trial is intriguing, "whether...
On behalf our Study group, I would like to thank EBN’s Editors for
their interest in our work.
In their review, major concerns regarding the
design and analysis of our study were raised by Drs Moralejo and Jull,
mainly because antiseptic protocols were randomised by services (called "clusters") but outcome was analysed by patients. The authors concluded
that while our trial is intriguing, "whether hand rubs and handwashing are
truly equivalent remains unclear". In my opinion, the fact that Drs
Moralejo and Jull misunderstood the design of our trial does not justify
that they unvalidate our conclusion.
The reason why we did not account for cluster randomisation is
simple: the design of our study was not a "cluster randomised trial", as
they incorrectly suggested. To be the case, each of the 6 services should
have been randomly assigned to one of the 2 protocols for the complete 16-month period of the study. In this case only, characteristics of each
service, such as teaching versus non-teaching hospitals or surgical team
experience, would have differentially affected outcome, because of
intracluster dependence between patients within each service.
In fact, each service alternated protocols monthly, so that they
equally contributed to include patients in both protocols, as shown in
Table 1 of our article. Initial randomisation of the services rather than
continuous randomisation of patients was not an error but a choice. Its
rational was clearly discussed in our article.
Finally, we must stand on our conclusion that handrubbing and
handscrubbing were equivalent in preventing surgical site infection.
We would like to thank Carlos Kusano Bucalen Ferrari for taking the time to respond to the Commentary by Violeta Ribeiro (EBN 2002; 5:57). Mr Ferrari gives us an interesting overview of the biochemical effects of several antioxidants in laboratory studies. These kinds of studies are frequently the starting point for developing new drugs and treatments but it is important to emphasise that the results of in vitro studies in labo...
We would like to thank Carlos Kusano Bucalen Ferrari for taking the time to respond to the Commentary by Violeta Ribeiro (EBN 2002; 5:57). Mr Ferrari gives us an interesting overview of the biochemical effects of several antioxidants in laboratory studies. These kinds of studies are frequently the starting point for developing new drugs and treatments but it is important to emphasise that the results of in vitro studies in laboratories are frequently not replicated when a treatment is trialed in the people the drugs are intended for. Therapies which appear to make sense from a physiological or biochemical perspective are often ineffective or harmful when tried in humans. We would therefore very much agree with the sentiments in the last line of the letter - more studies, and particularly clinical trials, are necessary to provide evidence for the clinical benefit of these therapies.
Professor Nicky Cullum
Centre for Evidence Based Nursing
Department of Health Sciences
University of York
Alcuin Teaching Building
York
If you would like to know more about systematic reviews why not read
the EBN Research Made Simple paper What is a systematic review? Available from:
Click here
If you enjoyed this EBN Notebook you may also like to read the EBN
Research Made Simple paper looking at Qualitative data analysis: a
practical example. This is available at:
Click here
For more information about Hypothesis testing and p values: how to
interpret results and reach the right conclusion see the EBN Research Made
Simple paper published in April 2013.
If you want to learn more about p values see EBN Research Made Simple
paper "What is a p value and what does it mean?" from April 2012.
For more information about Hypothesis testing and p values: how to
interpret results and reach the right conclusion see the EBN Research Made
Simple paper published in April 2013.
If you want to learn more about p values see EBN Research Made Simple
paper "What is a p value and what does it mean?" from April 2012.
If you enjoyed this EBN Notebook you may also like to read the EBN
Research Made Simple paper looking at Qualitative data analysis: a
practical example. This is available at:
Click here
Dear Editors
The study:
A home-based, nurse-delivered exercise programme reduced falls and serious injuries in people ³ 80 years of age. Robertson et al. Effectiveness and economic evaluation of a nurse delivered home exercise programme to prevent falls. 1: randomised controlled trial. [1]
appeared in both Evidence-Based Medicine [2] and in Evidence-Based Nursing.[3]...
It is well documented that Free radicals (FRs) and their Oxidative Reactions are implicated in more than 70 diseases and disorders [1,2], including inflammatory reactions, such as alergies and rheumatoid arthritis. As FRs and Oxidative stress are also implicated in many cell death processes [3], many scientific activities are being done to discover possible protective effects of the antioxidant therapy [1]. Today...
Dear Editor
Dr Parienti and colleagues have raised concerns [1] about a section of the commentary for which I am responsible. Their letter highlights the lack of a standard typology for trial design in clinical epidemiology. At the heart of this issue is not only what to call the different types of clinical trial, but how to analyse the results of each trial. Was the trial by Dr Parienti and colleagues a cluster randomi...
Dear Editor
On behalf our Study group, I would like to thank EBN’s Editors for their interest in our work.
In their review, major concerns regarding the design and analysis of our study were raised by Drs Moralejo and Jull, mainly because antiseptic protocols were randomised by services (called "clusters") but outcome was analysed by patients. The authors concluded that while our trial is intriguing, "whether...
If you would like to know more about systematic reviews why not read the EBN Research Made Simple paper What is a systematic review? Available from: Click here
Conflict of Interest:
None declared
If you enjoyed this EBN Notebook you may also like to read the EBN Research Made Simple paper looking at Qualitative data analysis: a practical example. This is available at: Click here
Conflict of Interest:
None declared
For more information about Hypothesis testing and p values: how to interpret results and reach the right conclusion see the EBN Research Made Simple paper published in April 2013.
If you want to learn more about p values see EBN Research Made Simple paper "What is a p value and what does it mean?" from April 2012.
These are both available at:
Cli...
Readers of this EBN Notebook might like the EBN Research Made Simple paper entitled: Selecting the sample. This is available at: Click here
Conflict of Interest:
None declared
If you enjoyed this EBN Notebook you may also like to read the EBN Research Made Simple paper looking at Qualitative data analysis: a practical example. This is available at: Click here
Conflict of Interest:
None declared
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