See this paper for an Uncertainty Analysis for Pressure Modules (PMM) used in 6270A and 2271A Modular Pressure Controllers. A number of these modules can also be used in the 8270A and 8370A Modular Pressure Controllers.
Here's the link to the paper on the Fluke Calibration web site,
http://us.flukecal.com/literature/articles-and-education/pressure-calibration/application-notes/guide-determining-pressure-
A pdf copy is attached to this article. Download with the link at the bottom of this article.
The uncertainty analysis refers to the QRPT uncertainty analysis, available here, PPC4 and other Q-RPT based pressure products - Uncertainty Analysis
Covers these models:
PM200
PM500 - added May 2018
PM600
PM630 - not yet included but same principles apply, pending update
BRM600-BA100K
See this document for 6270A Product Specifications
See this article for an example of calculating the uncertainty in absolute mode of an absolute PM600 module with the 1-year zero drift included, PM600 Absolute Mode Uncertainty - Understanding the RSS Formula
See this article if you're interested in tracking the calibration coefficients of your module(s) over time, Q-RPT, AutoZero tracking sheet for absolute model Q-RPTs