Accepted answer
2 weeks is 14 days, and the first question about any marker is whether 14 days is long enough for it to have finished moving. Lipase has a wide reference interval and a wider asymptomatic one, which makes an isolated value without symptoms a weak test in this setting. Against 14 days the marker is at or near the edge of its own settling time, so part of what you are reading is the transition rather than the destination. The second question is the denominator. Weight loss moves plasma volume, muscle mass and intake at once, and several of the markers on a routine panel are ratios with one of those three underneath them. Repeat before interpreting. A single value 14 days in, with no baseline drawn under the same conditions, is a number rather than a change — and nothing here is medical advice.
Before reacting to any single value, check whether it is outside the interval by an amount larger than the assay's own variation.
Same laboratory, same method, same time of day, same fasting state. Between-laboratory differences on several common analytes are larger than the changes people are trying to detect.
Timing matters per analyte: cortisol and testosterone are diurnal, triglycerides are postprandial, and creatinine responds to hydration and to recent training. Fixing the conditions removes most of the noise.
External quality assurance schemes document between-laboratory differences on common analytes that routinely exceed the size of clinically interesting changes.
Same laboratory, same time, same fasting state, or the comparison is not a comparison.
5Worth flagging that a mild enzyme elevation with a normal bilirubin is a different object from a rising one. – mg_per_ml 4 months ago 4This should be linked from the help pages. – lyoph_cake 2 months ago add a comment