PDCA as Personal Scientific Method

Definition

PDCA—Plan, Do, Check, Act—is the scientific method applied to personal work improvement. Form a hypothesis about what might improve your productivity or quality, test it over a defined period, measure the results, and then either adopt the change or try a different hypothesis. This replaces the common pattern of adopting productivity "solutions" without ever checking whether they actually worked.

In the Book

Markovitz opens Chapter 5 with the observation that most companies spin in a "plan-do-plan-do cycle" or worse, a "do-do-do" cycle—they never stop to check results. He asks provocatively: When your company reorganized to improve collaboration, did it work? Do you have measurements to prove it? Most don't. They just move on to the next initiative.

PDCA breaks this cycle. The book's hospital example is concrete: hypothesize that removing neckties (unwashed petri dishes of bacteria) will reduce infections. Plan: doctors wear no ties for April. Do: they follow the plan. Check: compare infection rates in April to previous months. Act: if infections drop, keep the policy; if not, reject it and form a new hypothesis.

Markovitz cites Bob Emiliani, a university professor who used PDCA over 13 years. Bob hypothesized that frequent small tests (quizzes) instead of two annual exams would improve student mastery. He tried it one semester, compared grades and student surveys to previous years (check), and adjusted lectures based on what worked (act). Students' grades improved. No ambiguity. PDCA is controlled experiment—facts, not gut feel.

Another example: Mark, an emergency department physician, noticed that the sickest patients didn't back up—the least ill patients clogged the system. He hypothesized that seeing patients in groups by complexity (one quick case, one straightforward intermediate case, one complex case together) would improve throughput. He experimented, checked results, and adopted the pattern as new standard work. "What would have previously been a very stressful situation was reduced to a routine event."

Why It Matters

Most productivity advice fails because it's never tested. Markovitz's critique is sharp: "providing the tools for improvement just isn't enough." People don't implement it, or they implement it without knowing whether it works. PDCA removes the guesswork. You learn what actually improves your work, not what a guru said should work. It also creates a habit of continuous improvement: once you adopt a change, you can immediately test the next hypothesis against that new baseline. This is how Toyota and Lean manufacturing excel—through relentless small cycles of experimentation, not big theoretical overhauls.