Evidence Based Practice is the combination of clinical expertise, patient values, and the best research evidence into the decision making process for patient care. (Sackett D, 1996). In the pre-hospital setting patient care can be explained as thoughtful consideration, interpretation and implementation of evidence based data which enables clinicians to treat patients with paramount care. (Ingersoll 2000). This essay will follow the critique framework developed by Caldwell et al (2005). It critically analyses a quantitative research article by O’Keefe et al (2010), investigating the survival rates and ambulance response times for out of hospital cardiac arrests. I chose this framework over others as it addresses both quantitative and qualitative research in a list of questions. It gives consideration to the research process and the different aspects of it, allowing me to evaluate the strengths and weaknesses of O’Keefe’s article.
Does the title reflect the content?
Griffiths (2012) states that the title should be as short as possible but should contain what the paper is about, including the design of the study undertaken. The title, “Role of ambulance response times in the survival of patients with out-of-hospital cardiac arrest,’ is relevant to the research performed but does not include the design of the study. Additionally, Blaxter (2010) states a title for research needs to be short and direct the attention of the reader onto significant aspects. The title contains fourteen words and therefore arguably not short. Conversely Sackett et al (1997) state a robust title should include the PICO (Population, Intervention, Comparison and Outcome) formula. The patients are clearly identified as those who experienced OHCA; however, there is no reference to any intervention or comparison and the outcome investigates the survival of patients only up until hospital discharge.
Are the authors credible?
Receiver judgments of communicator trustworthiness and especially expertise, are found to be significantly influenced by information concerning the communicator’s occupation, training and amount of expertise. (Hurwitz et al 1992). With no prior knowledge of the authors, readers would have had no experience from which to judge O’Keefe and the other authors credibility or trustworthiness. Although none of the authors are paramedics, they do have a background in emergency medicine making them credible authors. O’Keefe and Nicholl have had a number of national research studies published in the field of pre-hospital and emergency care and continue to have articles published, two articles recently published in 2016. Nicholl is an NIHR Senior Investigator, a fellow of the Faculty of Public Health, and also a Chartered Statistician and Fellow of the Royal Statistical Society. O’Keefe joined the Health Services Research Section of ScHARR in 1999 and has worked on a number of national research studies in the field of pre-hospital and emergency care research, including two NIHR funded national evaluations. (University of Sheffield.)
Does the abstract summarize the key components?
Varkevisser et al (2003) believe that summarising the significant aspects in the abstract of an article is essential due to allowing the reader to do a systematic comparison of different articles. The abstract states key components such as OHCA and the response times however does not mention how they were sampled or mention the survival rates of patients in correlation with ambulance response times.
Is the rationale for undertaking the research clearly defined?
The rationale is clearly defined in this research article as trying to improve patient outcomes for OHCA by investigating ambulance response times. Bettany-Saltikov (2012) state that authors should clearly present their rationale for research, emphasising any prior knowledge of the topic. The authors highlight the variation of survival rates from other countries worldwide further indicating to the reader the justification for undertaking the research. Woodside et al (2009) add that a clear rationale in a piece of quantitative research is vital for a good design in order to assess the variables. The title directly mentions survival rates and goes into further detail in the abstract highlighting percentage of patients that were discharged, giving the reader a clear impression of the rationale of the article.
Is the literature review comprehensive and up-to-date?
The literature review should provide sufficient understanding of the current theories and current bases of understanding. It should provide evidence to suggest the research question being studied is important and relevant. (Ross 2012). O’Keefe et al cite twenty-six research articles and at time of publication in 2010, the majority were over five years old, were one article dated back to 1990. The article mentions studies from seventeen different countries but only going into detail for two of these which is insufficient for a comprehensive study.
Are all ethical issues identified and addressed?
Emanuel et al (2000) state that the most important factor in ethics is the ability to improve health by means of research trials. Within this audit they assessed PRFs over a five year period to see if response times affected the outcome of OHCA. The articles states that the research was approved by twenty one out of twenty four committees. The authors have shown clear intentions, intending to help increase the chance of survival after cardiac arrest. The issue of gaining consent does not necessarily apply within audits, as Section 60 of the Health and Social Care Act 2001 states that confidential data can be used without the consent of the participants where work such as clinical audits is being undertaken in order to improve patient care.
Is the study design clearly identified and is the rationale for choice of design evident?
O’Keefe et al have chosen to present their findings using a quantitative method. Creswell (2003) states that quantitative research has the benefits of being conclusive, absolute and having specific, pre-determined questions allowing for clear-cut comparison. They have used tables and graphs to present their findings, the data is reliable, if research were carried out again similar results would be found. This therefore reduces the likelihood of bias. O’Keefe et al have clearly identified a study design in their article. They describe how they collected data from ambulance services annually for a period of five years, making this a retrospective cohort study.
Is there an experimental hypothesis clearly stated? Are the key variables clearly defined?
O’Keefe et al do not use an experimental hypothesis in this particular study. Marczyk et al (2005) state that an experimental hypothesis is mainly used within quantitative research that has a control group and an experimental group. There is no control group. It would be immoral to experiment on patients having a cardiac arrest, making this non-experimental therefore negating the need for an experimental hypothesis. Kothari (2004) states that identifying key variables within a study are fundamental because the results of the study are often observing, measuring and describing the relationship between two or more variables and that not identifying them can render the study. O Keefe et al identifies key variables such as place that the arrest occurred, whether bystander CPR was performed and the age of the patient.
Is the population identified? Is the sample adequately described and reflective of the population?
The study population needs to offer a clear definition as to who belongs to the study population and who should be excluded. (Eldredge 2014.) The population is clearly identified as 1161 patients who have had a cardiac arrest while out of hospital. Although resuscitation was attempted on 1258 patients they did not include 80 patients who suffered a non- cardiac related arrest. In 58 cases the patient arrested after crew arrived on scene and these patients had a higher percentage of survivability. Participants were recruited from four ambulance services however it does not state their geographical location raising the question is it reflective of the population as a whole? The urban ambulance services would have a lot higher survival rate as the transport to hospital times are reduced.
Are the results presented in a way that is appropriate and clear?
The results are presented clearly with sub-headings describing the effect of each variable on survival rates. The authors use charts and graphs to clarify the data in a way that is easily understandable and appropriate to the quantitative nature of the study. Fain (2013) states that results need to be presented transparently and accurately which the authors achieved. An audit was a suitable method for collecting data. It evaluates how well current practice is being carried out and where there is room for improvements to ensure the best care for patients
Is the discussion comprehensive?
The question asked in the title if whether response times affect survival rates of out of hospital cardiac arrests is not answered in the discussion section, it focuses more on ethics, sampling and different relevant studies is lacking and not sufficient to be comprehensive.
Are the results generalizable?
Melynyk and Fineout-Overholt, (2015) state that generalisability can be defined as being able to extrapolate results from a research population and apply those results to the wider population. In this article the population is elderly, aged over 60 and the authors do not state which parts of the country the research data was obtained from therefore arguing the results are not generalizable.
In conclusion, O’Keefe’s paper examining the relationship between ambulance response times and survival rates in OHCA has shown that a reduction in response times do improve outcomes. However, the article has a number of limitations that inhibits its ability to be applied to practise. Due to the design of the study, it is not clear if the findings can be applied to all patient groups, in all geographical environments and not all variables have been accounted for. This study was not able to discriminate between the effect of outcome in OHCA of the response time v the interventions performed by crews. Further research would be required before the recommendations can be implemented into practice.