{"id":62898,"date":"2016-01-05T14:01:43","date_gmt":"2016-01-05T19:01:43","guid":{"rendered":"http:\/\/1boringoldman.com\/?p=62898"},"modified":"2016-01-07T22:17:09","modified_gmt":"2016-01-08T03:17:09","slug":"john-henrys-hammer-continuous-variables-i","status":"publish","type":"post","link":"https:\/\/1boringoldman.com\/index.php\/2016\/01\/05\/john-henrys-hammer-continuous-variables-i\/","title":{"rendered":"john henry’s hammer: continuous variables I…"},"content":{"rendered":"\n

<\/a>John Henry was an American Folk Hero. He was a steel driving man<\/font><\/em> in the era when they laid the railroad lines by hand. In one version of the legend, when they introduced a steam-driven hammer to cut the tunnels, John Henry and the new-fangled machine were pitted against each other. John Henry won with his hammer, but then He laid down his hammer and he died, Lord Lord. <\/font>He laid down his hammer and he died<\/font><\/em>…<\/p>\n

That’s the situation for most of us vetting the modern industry-funded Clinical Trials. The company statisticians have PhDs and use powerful [and expensive] software like SAS or SPSS running Linear and General Linear models capable of sophisticated analyses. We’re like John Henry, armed with only a computer calculator, a spreadsheet program, and scattered Internet Calculators – oh yeah, they have the data and we have only the proxies that we can gather from the published papers. <\/p>\n

Frankly, I don’t know how many clinicians even want to know how to evaluate the reported findings in these clinical trial articles themselves. The waves and raves of psychopharmacology that started decades ago are finally on the wane, so the period when such skills would be of general use may be passing. But I think I see it as Continuing Medical Education. We’re already in an era where data of all kinds is a part of our daily medical practice – with the electronic medical records, the "Os" [HMOs, PPOs, etc], and population studies, data comes from every direction. Sailing between the Scylla of cost containment and the Charybdis of profit-based medicine will become increasingly difficult without a practiced intuition about all kinds of data and data processing. So I’m inclined to continue to pass on the few tricks of the trade that have been handed over to me in these last few years. To borrow a term from some of my colleagues in the recent Study 329 project, it’s just part of the healthy skepticism<\/a><\/em> that should accompany any medical career. And the term evidence-based medicine<\/font><\/em> is meaningless if you’re not fluent in the ways and means of evaluating evidence for yourself. Here are a couple of methods if you don’t already have some:<\/p>\n

METHOD 1 – the spreadsheet<\/font><\/strong>:<\/p>\n

    \n

    So, for starters, here’s a simple spreadsheet I made a couple of years ago that’s been helpful along the way. You can download it for your own use by clicking here<\/a>. You can save it to your download folder, or open it and then save it wherever you want [it’s a small file – about the size of a graphic]. If you’re not spreadsheet literate or don’t have one on your computer, go down the page to METHOD 2 – the calculators<\/font>]:<\/p>\n

    <\/p>\n

    If it looks familiar, it’s what I used to fill in the empty spaces in the table in in the land of sometimes[5]<\/sup>…<\/a> from the Brexpiprazole trials in Schizophrenia. This one:<\/p>\n\n\n\n\n\n\n\n\n\n\n\n
    BREXPIPRAZOLE Trials in Schizophrenia<\/font><\/strong> <\/p>\n
    <\/sup><\/td>\n<\/tr>\n
    STUDY<\/sup><\/font><\/strong><\/td>\nDRUG<\/sup><\/font><\/strong><\/td>\nMEAN<\/sup><\/font><\/strong><\/td>\nSEM<\/sup><\/font><\/strong><\/td>\nσ<\/sup><\/font><\/strong><\/td>\nn<\/sup><\/font><\/strong><\/td>\np<\/sup><\/font><\/strong><\/td>\nd<\/sup><\/font><\/strong><\/td>\nlower<\/sup><\/font><\/strong><\/td>\nupper<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    Correll
    et al<\/sup><\/td>\n    		placebo<\/sup><\/td>\n-12.01<\/sup><\/td>\n1.60<\/sup><\/td>\n21.35<\/sup><\/font><\/strong><\/td>\n178<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n<\/tr>\n
    0.25mg<\/sup><\/td>\n-14.90<\/sup><\/td>\n2.23<\/sup><\/td>\n20.80<\/sup><\/font><\/strong><\/td>\n87<\/sup><\/td>\n0.3<\/sup><\/td>\n0.14<\/sup><\/td>\n-0.120<\/sup><\/font><\/strong><\/td>\n0.393<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    2mg<\/sup><\/td>\n-20.73<\/sup><\/td>\n1.55<\/sup><\/td>\n20.80<\/sup><\/font><\/strong><\/td>\n180<\/sup><\/td>\n<0.0001<\/sup><\/td>\n0.41<\/sup><\/td>\n0.204<\/sup><\/font><\/strong><\/td>\n0.623<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    4mg<\/sup><\/td>\n-19.65<\/sup><\/td>\n1.54<\/sup><\/td>\n20.55<\/sup><\/font><\/strong><\/td>\n178<\/sup><\/td>\n0.0006<\/sup><\/td>\n0.36<\/sup><\/td>\n0.155<\/sup><\/font><\/strong><\/td>\n0.574<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    Kane
    et al<\/sup><\/td>\n    		placebo<\/sup><\/td>\n-13.53<\/sup><\/td>\n1.52<\/sup><\/td>\n20.39<\/sup><\/font><\/strong><\/td>\n180<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n–<\/sup><\/td>\n<\/tr>\n
    1mg<\/sup><\/td>\n-16.90<\/sup><\/td>\n1.86<\/sup><\/td>\n20.12<\/sup><\/font><\/strong><\/td>\n117<\/sup><\/td>\n0.1588<\/sup><\/td>\n0.166<\/sup><\/font><\/strong><\/td>\n-0.067<\/sup><\/font><\/strong><\/td>\n0.399<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    2mg<\/sup><\/td>\n-16.61<\/sup><\/td>\n1.49<\/sup><\/td>\n19.93<\/sup><\/font><\/strong><\/td>\n179<\/sup><\/td>\n0.1488<\/sup><\/td>\n0.153<\/sup><\/font><\/strong><\/td>\n-0.054<\/sup><\/font><\/strong><\/td>\n0.360<\/sup><\/font><\/strong><\/td>\n<\/tr>\n
    4mg<\/sup><\/td>\n-20.00<\/sup><\/td>\n1.48<\/sup><\/td>\n19.91<\/sup><\/font><\/strong><\/td>\n181<\/sup><\/td>\n0.0022<\/sup><\/td>\n0.321<\/sup><\/font><\/strong><\/td>\n0.113<\/sup><\/font><\/strong><\/td>\n0.529<\/sup><\/font><\/strong><\/td>\n<\/tr>\n<\/table>\n

    As most of you already know, the cells in your spreadsheet program [I use the free Open Office<\/a> Calc] can hold one of three things: a number<\/font>, some text<\/font>, or a formula<\/font> that shows the results of operations on the data in other cells. So the seven columns on the left are just empty cells for Data Labels and Data Entry. The eight cells on the right hold formulas that compute the results. <\/p>\n

    Here’s what they hold [from left to right]:<\/div>\n