MED5539
Clinical and Research Laboratory Skills
Proforma Lab Report
The standard curve and method comparison
Word counts given below are as a guide only. They are not a requirement that should be met precisely. Please expand the boxes below as necessary.
Title
For a lab report the title is a summary/description of what you set out to achieve in the practical. The reader wants to know what to expect the report will be about. [In contrast, the title of a research paper often focusses on the main result or advance in knowledge to catch the reader’s eye.]
Abstract
Your report should have a precis of your report as an abstract. You want to cover all the main sections (background, aims and objectives, method, results and conclusions) but very briefly. A good abstract contains some hard data e.g. what was your CV and the class CV? How well did the Bradford and Lowry methods agree (quote data like bias, limits of agreement etc). Paradoxically the abstract is best written last when you have written all the detail of the other sections.
Introduction
Your report requires some background information so that the reader understands all the information you will provide and discuss later. One way of thinking of it is that nothing should come as a surprise to the reader of your report (other than the actual results!) because you have fully explained what you are trying to do, why and by which methods in the introduction. So here for example you might want to talk about how the assays work, how assays can be compared and what the relevance of what you are doing is to the learning outcome of the course i.e. why it is important?
Aims and objectives
State the aim of your experiments and give the objectives that you completed during the practical. Don’t just copy them out of the Course Information Document, reword them in your own words.
Methods
Methods of reports are not written as steps in a protocol. They are summarised in continuous prose. It is quite difficult to summarise methods concisely and this is a useful skill to learn. Have a look at the methods section of a research paper and you will get an idea of how they should be written. The idea is that enough information is provided so that another person could come along and replicate your experimental protocol. Pay attention to volumes, concentrations and amounts. Giving just a volume but no concentration of a solution is useless. Manufacturers of equipment and suppliers of chemicals are usually provided, though this is not necessary here. It often helps to use subsection headings in this part of the report.
Results
Here you should systematically summarise all the data you have collected and present it in an easy to understand way using Tables and Figures that you refer to in chronological order in the text after their first mention. You should write a narrative text explaining what you observe from your data. In the results statement of observations are made only, you do not try and explain what they mean at this stage. Summarised, rather than raw data should be presented. Pay attention to the presentation of your tables and figures. Are they annotated and labelled correctly? Are the correct units shown? Have you provided sufficient detail on sample numbers etc? Have you provided a Table or Figure legend (again refer to a research paper if you are not sure what goes into a legend)
Insert below the text, tables and figures that you think best explain your data:
1. Show your standard curve for whichever assay you carried out and comment on it in your narrative text.
2. Look at your own QC data – how might you show that graphically? Note the level that you measured and the CV you obtained.
3. Compare your own QC data to that of the whole class (for the same assay) looking at the mean values and the CV.
4. Compare the whole class QC data (mean values and CV) for the Bradford and the Lowry a) between each assay and b) with the autoanalyzer data. How might you present this information? How might you test for statistical difference?
5. Compile the class data for the unknowns (A – U) for both the Bradford assay and the Lowry assay. Are there any samples you would exclude? If so, why?
6. Plot a Bland Altman plot to compare the two sets of data (after excluding any you think should be excluded). Refer the Bunce 2009 American Journal of Opthamology 148(1); 4-6 paper on Moodle.
7. What is the bias between the measurements? Is it statistically significant? What are the confidence intervals of the bias?
8. What are the limits of agreement (LoA) between the two tests?
9. Look at the shape of your Bland-Altman plot and comment on that.
Insert Your Tables and Figures here in number order.
Discussion
The first paragraph of your discussion summarises what you found overall. Then in following paragraphs you comment on your results and your interpretation of them. e.g.
How good was your standard curve?
How good was your CV?
How did it compare to the class CV for each assay?
Compare the performance of the two assays both in terms of CV and in terms of the Bland Altman analysis.
What were the strengths and limitations of your experiment and analysis? How could the experiment have been improved?
Finally add an overall conclusion paragraph which summarises your key findings and how they fit into the context of wider research. Why is what you studied in this practical important?
References
Provide a list of references for information you have provided in the report (most commonly in the introduction, methods and discussion). You should not need any references for your results section. A numbered referencing style. such as Vancouver is commonly used.