CMHL1001 Semester Notes PDF

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CMHL1001 Semester NOTES Topic 1 – Evidence-based practice Learning outcomes:  Recognise credible and non-credible sources of evidence.  Select suitable sources of evidence that are appropriate to your situation (as student/ professional)  Explain the principles of evidence-based practice  Generalise principles of evidence-based practice to your own profession Definitions: Reliability – The quality of being consistent and to what degree this consistency sits at Validity – The quality of being logically or factually sound Provenance – The origin of where the information came form Meta-analysis – Statistical procedure for combining results from existing quantitative studies with measured outcomes, effectively increasing sample size and precision The meaning of ‘Evidence-based practice’ - A practice that is supported by scientific evidence, clinical expertise and client values that will have significantly better outcomes than ‘standard’ care for your patients - ‘The conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients’ - EBP should be visualised as a three-pronged and overlapping approach (Triad approach): Research evidence, clinical expertise and patient values o The best possible research evidence: The higher the level of evidence, the better the evidence is o Clinical expertise: takes into consideration your experiences, both personal and professional, to help guide you in how to best care for your patients o Patient values and preferences: When treating patients, their values should be the first thing that you take into consideration, as there is no point in suggesting treatment’s they are not able to engage with - If you are a health practitioner working in rural or remote locations, you also need to take into account whether ‘best practice’ is available – you might have to seek alternative treatments because the evidence-based practice is not available

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People are also apprehensive because there are a lot of hard, new words to learn which makes EBP almost like a new language or vocabulary. It is important to know that everything in EBP can be broken down to simpler steps People may not see the point in EBP as, unfortunately, the best practice is not always available or followed. In the United States in the 1970s, only 10-20% of all health technologies then available were evidence based; in the 1990s this figure increased to 21%.

WRONG types of decision making - Decision making by: o Anecdote o Press cutting o Expert opinion o Cost minimisation

Before you start: formulate the problem - 3 components a good clinical question should include o Define precisely whom the question is about o Define which manoeuvre you are considering in this patient, and, if needed a comparison manoeuvre o Define the desired, or undesired, outcome

Topic 2 – Research design overview and making sense of peer reviewed articles Learning outcomes:  Compare and contrast qualitative and quantitative research designs  Identify the following within levels of evidence: o Primary/ secondary research o Experimental/ observational designs o Qualitative/ quantitative designs  Articulate what determines the study’s design  Apply the PICO, PEO or PICo to appropriate research designs  Use the PICO, PEO or PICo to: o Consolidate key information from the study’s abstracts o Formulate a research question o Formulate a null and alternate hypothesis

Compare and contrast qualitative and quantitative research designs - For quantitative studies, you may phrase your research question as: is there a relationship between intervention/ exposure and outcome (compared to comparison) in population? - For qualitative studies, you may phrase your research question as: what is the interest of population in context? Qualitative Research - Qualitative researchers seek a deeper truth - They aim to study things in their natural setting, attempting to make sense of, or interpret, phenomena in terms of the meanings people bring to them, and they use a holistic perspective which preserves the complexities of human behaviour - They argue that a counting and measuring approach (quantitative) limits the results of a study - Qualitative research years ago was reserved for social scientists – it is now increasingly recognised as being a prerequisite for the quantitative research to provide more depth and meaning to research - Uses the PICo tool o Population or problem o Interest o Context What distinguishes qualitative from quantitative? - Quantitative research begins with a hypothesis, which then, through measurement, generates data and, by deduction, allows a conclusion to be drawn - Qualitative research is different – begins with an intention to explore a particular area, collects ‘data’ (observations, interviews etc), and generates ideas and hypotheses from these data largely through inductive reasoning - The strength of quantitative approach lies in its reliability (repeatability) - The strength of qualitative research lies in its validity (closeness to the truth) - The validity of qualitative methods is often improved when the researcher incorporates 3 approaches to their research o Use of more than one method used in combination (triangulation) o Thinking carefully about what is going on and how their own perspective might be influencing data (reflexivity)

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Including more than one researcher to help with the analysis of the same data (to demonstrate inter-rater reliability)

How and why quantitative research is done - To understand this, it helps to contrast quantitative methodologies with qualitative research

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Thus, we can see quantitative research relies on tightly planned sampling and data collection methods, rigorous numerical measurement of amounts or categories, and statistical presentation of results with a view to answering a specific question

Types of quantitative research designs Intervention studies - The researchers do something (the intervention) with the study participants to bring about a change. The researchers then measure the amount of change after the intervention compared with before to see the effect - Among intervention studies there are experimental designs, which include randomised controlled trials and non-randomised controlled trials – experiment and control group - Experimental designs used in clinical trials are summarised using the PICO system – it is good for asking focused clinical questions o Population o Intervention o Comparison o Outcome measures Observational studies - Researchers allow events to happen naturally - Researchers observe what happens rather than attempting to instigate changes

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These studies collect information without the researchers doing anything to influence the data These studies are conducted when interventions are impractical or unethical Systematic reviews are a specialised type of research in which a selection of existing quantitative studies is appraised, and their results combined statistically to give a summary finding Systematic reviews save practitioners the time and effort to locate, read, appraise and integrate results from numerous research reports They are conducted according to procedures designed to reduce the risk of bias PEO is applied to observational studies (for people who are exposed to something) o Population o Exposure o Outcome

Identify the following within levels of evidence: Primary/ secondary research - II-V is primary - I is secondary Experimental/ observational designs - II and III-1 is experimental - III-2 to V is observational Qualitative/ quantitative designs - Anecdotes are qualitative - II to IV is quantitative

Articulate what determines the study’s design - The research question

Apply the PICO, PEO or PICo to appropriate research designs PICO is applied to an experimental design in quantitative research - Population - Intervention

- Comparison/ control - Outcome PEO is applied to an observational design in again quantitative research - Population - Exposure - Outcome PICo is applied to qualitative research - Population - Interest - Context

Hypothesis - A null hypothesis is a statistical hypothesis in which NO significant difference (ie: relationship) exists between the set of variables. It is the original or default statement, with no effect, which is represented by H0 (H-zero). - The alternative hypothesis is what the researchers are trying to test if their prediction is true, it is represented by HA or H1. - Remember that qualitative studies are hypothesis-generating. Hence, there are NO hypothesis statements for qualitative studies. - A hypothesis statement may be written as: o H0 : There is no difference/ relationship between the intervention and the outcome (compared to the comparison) in the population o HA/ H1 : There is a difference/ relationship between the intervention and the outcome (compared to the comparison) in the population.

Topic 3: Sampling The terminology around sampling - Theoretical population (or target population) o Should be seen as the larger group that the researcher wants to generalise their findings to o i.e. I am conducting this study because I want to apply my findings to this group - Study population (or accessible population) o The population that the researcher has access to draw participants from o Typically, the study population is a subset of the theoretical population from which the sample is taken – this is done to either maximise efficiency, or because it's not possible to access entire theoretical population - Sampling frame o In order to identify a sample, a sampling frame is required o A sampling frame is a detailed list of all participants, which can include people, locations or events in a population – usually relates to the study population - Sample o The sample is the group of participants who have been chosen to be of the current study - Sampling o Sampling is the process of selecting participants, so that researchers can attempt to generalise their results back to a theoretical population

Types of sampling

Probability Sampling - The main characteristic is the random selection of participants from a population - This approach ensures that all members of a target population have a known chance of being selected - Although probability sampling strategies do not guarantee the generation of a truly representative sample, the random selection of participants from a theoretical population means that any differences between the population and the sample are due to chance - Compared to non-probability sampling, probability sampling is more likely to result in a representative sample with reduced sampling errors and bias - The types of probability sampling include:

Non-Probability sampling - Non-probability sampling does not involve the use of randomisation, used for convenience - Participants are chosen in a process that does not give all participants in the population an equal chance of being selected - Used in qualitative research designs as they are purposely seeking out particular participants to engage in the study - There are several types of non-probability sampling techniques

Sampling Error - Measurement error refers to errors that take place with the data, whereas sampling error occurs when the group of participants chosen is inadequate or not random enough - There are two types of sampling error: o Random errors  Are common and occur randomly in a sample as a result of under or over representation of certain groups  The likelihood of random errors can usually be reduced by increasing the sample size o Systematic errors  Are more difficult to handle because their likelihood cannot be reduced in this way ^^  They usually occur as a result of inconsistencies or errors in the sampling frame; hence the reason researchers should take care when designing the sampling frame  This highlights the importance of an accurate sampling frame: inaccuracies will lead to systematic errors that cannot be corrected through increasing the sample size

Calculating Sample size Quantitative research - The required sample size should be calculated during the design and planning of a research study - A quantitative research report should outline the required sample size and the way in which it is calculated - The presence of this increases one’s confidence in the study’s findings for an important reason: it quantifies the likelihood that the results are a chance finding in that sample and not a ‘true’ finding in the target population - PROBABILITY o TYPE 1 ERROR: when you think there is a correlation, but in fact there is NOT. May be due to chance. Here, p...