hey i did my epq last year, it was about depression and alternative medicine so sort of similar in the medicine theme i guess!
My first piece of advice would maybe be to see if you could specify your title even further, i know it may seem like your current question is pretty specific, and it is, but i think you may find that there are multiple treatments for parkinson's and different types for different symptoms. You may also find it hard to evaluate the effectiveness of them because surely they'll all be pretty effective since they're approved for treatment of parkinson's (as in a non-effective drug wont be approved) so you'll have to specify the criteria you will be assessing effectiveness against, and this may come into your title. Maybe you could consider looking into one specific treatment (perhaps a controversial one?) and the history, development, pros, cons, costs and personal opinions of that treatment to conclude whether, in your opinion, it is an effective drug? Alternatively, you could specify in your introduction, for example, a few specific treatments (maybe 4/5) and compare them against each other and give your opinion on which you think is best.
In terms of structuring your work my recommendation would be to write out specific tasks you need to accomplish. For example, you could have 'research' 'planning' 'writing' and 'presentation' as your 4 main tasks, then subdivide those into more tasks. To do this you'd need to specify exactly what you want to discuss in your essay, (see para above) and based on that write out exactly what things you'll be researching, this will save you a lot of time! So, an example could be for 'research', your sub tasks are, research about: What parkinson's is (for introduction), a criteria to measure effectiveness, main treatments, professional opinions, patient opinions. Then for each these, you divide further, for example, for 'main treatments' you could sub-divide into treatments 1,2,3... Etc and look into: History/discovery, mechanism of action, resultant effect on patient, side/effects, effects on patient socially (these will all depend on the criteria you are measuring effectiveness against and also how much detail you want to go into). You'll find that these divisions and sub-divisions will hopefully form the headings of each paragraph / section in your essay and help with structure, though you will definitely need to edit it of course.
Your presentation will be super easy to do once you've written your essay because you'll know everything about your question so i wouldn't worry too much about that yet. If you can get access to a mark scheme (i think they're available online?) that would really help you there in terms of knowing exactly what you need to include.
The main thing to remember is that a lot of your marks come from your 'journey' how you get from the drawing board to the final product, that's why things like planning, managing tasks (see para 2) and reflecting on what you've done / what you'll do next is so important. Make sure you keep a thorough log of your work, it'll come in handy when evaluating your process and hopefully will hitch you some marks too.
I hope this helps! Let me know if you need any more advice or if you have any questions
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