Haematology Assay Requirements

This page will be updated as new tests become available and outmoded ones are removed.  It should not be regarded as exhaustive or static.

Reference (or Therapeutic) ranges for commonly requested tests are included with the reported results, and are also available on the Pathology Computer System. These are derived from a combination of Haematology text books, locally derived ranges and those recommended by manufacturers of equipment used with the laboratory. If you would like further information on the origin of reference ranges, please contact the Blood Sciences Manager on 01271 322329 (or ext. 2329 from within the hospital.)

Adult Tubes
TubeMinimum Volumes Required
GoldGel tube1.5ml
PurpleFBC (can include RET+NR+film)1ml
PurplePlasma Viscosity4ml
PurpleHb A1c (GHB)1.0ml
PurpleMolecular Genetics8.0 ml (2 full tubes)
BlueClotting Screens2.7 ml (must be full to line)
NB. A single FULL PURPLE tube only is required for FBC +GHB +Plasma viscosity
Paediatric Tubes
PurpleFBC (can include RET +NR+ film)0.5ml
BlueClotting Screens1.0 ml (must be full to line)
(G/A)Reported with gender and/or age related reference ranges


The minimum volumes above relate to routine screening tests. Please contact the laboratory for minimum volumes for non-routine investigations.

TestReference Range (Fasting Adult)
Full Blood Count
Purple Tube
Turnaround Time: 2 hours
HaemoglobinM 130 – 170g/L (G/A)
F 115 – 160g/L (G/A)
WBC4.0 – 11.0 x 109/L
Platelets150 – 400 x 109/L
MCV80 – 100 fl (G/A)
MCH27 – 32 pg
MCHC300 – 360 g/L
HctM 0.4 – 0.55 (G/A)
F 0.35 – 0.45 (G/A)
RBCM 4.5 – 6.5 x1012/L (G/A)
F 3.8 – 5.80 x1012/L (G/A)
RDW12 – 16 % (CV)
RETICS<2.0% 23 – 82 x109/L
Neuts1.8 – 7.5 x109/L
Lymphs1.0 – 3.5 x109/L (G/A)
Monos0.1 – 1.0 x109/L
Eos0.04 – 0.4 x109/L
Baso0.00 – 0.25 x109/L


TestReference Range (Fasting Adult)
Blue tube
Turnaround Time: 2 hours
PT13 – 16s, INR 0.9 – 1.1 (G/A)
A.P.T.T.25 – 36s, APTTR: 0.82 – 1.18 (G/A)
Heparin TherapyAPTTR: 1.5 – 2.5, FXa 0.35 – 0.7 units/mL
FibrinogenClauss 190 – 410 mg/dL
Thrombin TimeControl time +/- 3s
D Dimers<150 ng/mL
VTE cut off ≤ 50 years of age: 250 ng/mL
> 50 years of age:  Age adjusted



Tube Colour

Reference Range (Fasting Adult)

*Average Turnaround Time (TAT)


Bone Marrow ExaminationReported by Consultant Haematologists who then directly act on the results. Final completed report may appear much later.To be arranged with Consultant Haematologist only
CD4 lymphocyte countPurple 24 hrsFresh specimen required
ESRBlack top – BD SeditainerM <12 (G/A) F <15 mm/hr (G/A) 2 hrs Must be delivered to lab within 4 hours of collection
Factor V LeidenBlue14 daysReferred to Exeter for analysis
Coagulation Factors II, V, VII, VIII or IX etcBlue 5-10 days depending on factorContact lab first Fresh specimen required
FibrinogenBlue 2 hrs
GHB (Haemaglobin A1c)Purple 8 hrs
Glandular Fever TestPurple 1 day
G6PDPurple 5 days
Haemoglobinopathy (HPLC)Purple 3 days
Haemoglobin A2Purple 3 days
HFE genesPurple x328 daysReferred to Exeter for analysis
HLA B27Purple 20 daysReferred to Exeter for analysis
INR (Warfarin Control)Blue 2 hrs
Intrinsic Factor Antibody  (IF)GoldTested in a batch – may take up to 1 month.If test required sooner, contact laboratory
JAK 2Purple14 daysReferred to Exeter for analysis
Lymphocyte SubsetsPurple10 daysReferred to Bristol for analysis
Malaria screenPurple Verbal report within 2 hours, final report follows laterFresh specimen required.
Suspected malaria is a medical emergency so samples should arrive as soon as possible in the lab – no later than the same day. If a negative result is returned and malaria is still suspected it is recommended that the test should be repeated on the next two consecutive days preferably during a temperature spike.It is important to state in clinical summary which countries have been recently visited.
PNH ClonePurple14 daysReferred to Bristol for analysis
Prothrombin Time  (PT)Blue 2 hrs
Prothrombin MutationBlue14 daysReferred to Exeter for analysis
Pyruvate Kinase  (PK)Purple10 daysReferred to Kings, London for analysis
Sickle Cell TestPurple1 – 2 days
Thrombophilia ScreenPurple & Blue x 3, GoldBatch tested once per month onlyFresh specimens required. Contact lab to discuss guidelines for testing.
Viscosity (Plasma)Purple 1.50 – 1.72 cps 5 hrs
Von Willebrand ScreenPurple x 1, Blue x 228 daysReferred to Exeter for analysis. Fresh specimens required

*The turnaround times shown are the average time taken (during normal working hours), from the specimen details being entered in the pathology computer system to the result being available to view electronically on the same system.  In addition it takes an average of 27 minutes  from the time specimens are delivered to the Pathology Dept to the time they are entered on the computer system. This time should be taken into account when considering total turnaround times for results to be made available. The time taken from collecting the specimen from the patient to delivery to the Pathology dept is not included in the quoted turnaround times above. Please contact the Pathology Quality Manager on 01271 335758 to discuss any aspect of analysis turnaround time. Following discussion with the Laboratory, URGENT samples, once received in the laboratory, are fast-tracked and reported sooner than those times shown above. Note: If printed, information is only valid on day of printing.

Last updated: February 1, 2021