More boring epidemiology.

So I try to introduce tidbits of other things into each lecture. Here, I relate how my grieving is lessened by the dear hearts of the young ladies in the busy beaver front row of the class. Very busy beaver. The loss, over just one month, of both of two wonderful kitties, weighs heavily on this otherwise hardened racist/sexist/multiphoboc Vierk heart. Miss Angel, huntress extraordinaire Maine coon cat, still presenting the women next door with all sorts of prey---voles, moles, mice and yes, the odd chipmunk as well---even during her frail last days. And huge calico Miss Lilly, who left us just yesterday, community greeter suprema, who on her last days, nearly blind, and barely still able to walk, sat on the front lawn in the warm mid spring sun, allowing passers by to scratch her on the favorite spot, under the chin. Purring right to the very end.
And how about these young budding pubic health students, now numbering almost 20, in their loose blouses and short skirts, all with the flashy red FM heels a going, informing me of their great sacrifice to help with the C-19 pander demic. It brought tears to these old eyes to hear that each and every one of these civic minded angels, is forgoing the use of undies, while sitting up front with your epididimis prof, just so that the fabrics can be better used for masks in the war against the great enemy, the deadly virus, as now called by our dear leader, Mr. Trump. With youth such as this, all I can say is,--- what a country! Chases away the kitty loss blues.But enough digression.
Now then, just how does evidence emerge from Epid? Again there are several levels of validity of such evidence, corresponding to the designs of the respective study approaches. At the most basic level, as with our cousin scientists, the demographers, descriptions of populations of individuals, some quite sophisticated, can yield very useful information. From predicting the clinical/hospital needs of a community, as in Health services Epid, to generating novel hypotheses, for analytical investigators, this research is vital. With these data, the more analytically minded crowd can employ various study designs, to explore the relationships between health/disease in these populations, and various factors of interest. And here's the kicker. In the more natural sciences, one can compare groups of lab animals, both control and groups exposed to the factors under study, PROSPECTIVELY, and see where the cards fall. But in Epid, methods exist to perform such investigations using historical data, as well as going forward.
The scope of these designs are beyond this course level, but your teacher would be happy to explain all of them, in his office, after class, but only to students, sequentially, one hour each, as individuals. Here, these approaches however will be named, so google away. Again, from most basic, to sophisticated, these include: ecological (correlations only) designs; cross sectional (lacking time dimensionality) investigations; case control studies-enabling the investigation of historical relationships, if only for one illness at a time; cohort designs, both forward and backward looking, by analogy with research with lab animals. And sometimes, these approaches can be combined, as in nested case control within cohort studies, say of defined worker populations.
Now the so called gold standards of these investigations are the various types of clinical trials, which strictly speaking, takes us into the field of clinical Epid. Often described as multi arm, randomised, blinded, power driven, etc., investigations,-- these are used to study the efficacy of medical interventions, such as new drugs, and diagnostic and surgical technologies. And taking all of this now to the realm of public health, we see the community clinical trials, which often are useful for policy decisions. Next time, this leads into the topics of epidemics.
By the way, my lovely beavers, the perfumes are great. class over.