I'm running a presence absence test with qPCR using TaqMan probes for a number of fish species. The goal is just to know if the fish is present or absent. When I run all my primer sets (8 total) my efficiency and R^2 values are not within the acceptable range (some low, some high). My question is: a) does anyone have tips on improving efficiency (without changing primers and probes) and b) for a presence/absence test would one be required to report efficiency/R^2 in a paper? ( I realize these things help identify a good qPCR reaction vs. a bad or unreliable one, but does it matter in a presence/absence survey?)