This step-by-step video clearly demonstrates the correct technique for the execution of the most commonly used manual technique in the diagnosis of bleeding disorders: the one-stage assay for FVIII. Supplementing the Lab Manual written protocol (Section 23), it also explains the theory behind the assay, details the important reagents, discusses the challenges posed by limited resources, and works through the plotting and interpretation of a series of typical diagnostic cases. The accompanying searchable transcript links to the individual sections of the video. A blank one-stage FVIII assay record sheet, log-log graph paper, and log-linear graph paper are also provided for free download.

Instructions

Click on the player below to start the video, make sure that your computer speakers are turned on to hear the narration. Below the player is a searchable transcript. Enter a keyword in the search field to identify all the points in the script where it is mentioned. Click on the preceding section title to jump to that point in the video. A list of abbreviations can be found at the end of transcript. Click on the icons below to download the supplementary materials: one-stage FVIII assay record sheet, log-log graph paper, and log-linear graph paper, and Section 23 of the Lab Manual, Factor Assays Based on APTT (One-Stage Assay of FVIII:C, FIX, FXI, or FXII).