What makes a blood test accurate
Three things decide whether a result can be trusted: the laboratory, the sample and the interpretation.
The laboratory. In the UK, medical laboratories are accredited by UKAS against ISO/IEC 15189, the international standard for medical testing. Accreditation means the laboratory's methods, equipment, staff and quality control are independently assessed. Randox Clinical Laboratory Services, which analyses our samples, holds this accreditation (UKAS Lab ID 9329).
The sample. Most errors happen before the sample reaches the analyser: a sample taken at the wrong time, not fasted when it should have been, left too long before processing, or damaged during the draw. A clinic sample taken by trained staff and couriered the same day avoids most of these problems.
The interpretation. A number is only useful if it is read in context. Reference ranges differ slightly between laboratories, and age, sex, medication, recent exercise and illness all shift results.
Private versus NHS
The analysis itself is comparable when both laboratories are accredited. The differences are in what is tested and who reads the result. NHS tests are chosen by a GP for a specific question; private tests are chosen by you and can be broader. Your GP can act on a private report from an accredited laboratory, although they may repeat a test before making a clinical decision.
Home finger-prick kits
Home kits can be accurate for many markers, but some, such as a full blood count or certain hormones, are more reliable from a venous sample, and small capillary samples are more likely to be rejected. A clinic draw gives the most reliable result for a broad panel.
At Omnia
Every sample at our Chiswick clinic is taken by trained staff, sent to Randox the same day and reviewed with you by a practitioner. See every test and price, or start with Omnia Essential (£90).