Laboratory diagnostics is the testing of samples from the body, such as blood, urine or tissue, to find out what is happening inside it. Most medical decisions depend on a lab test. A doctor checks your blood sugar before treating diabetes, counts your blood cells to look for an infection, and tests a tumour sample to choose a cancer medicine. In India, these tests are done by hospital labs, by large diagnostic chains and by small neighbourhood labs.
Here is a typical journey. Your doctor in Indore asks for a blood sugar test and a complete blood count, because you have been feeling tired. You book the tests on an app. At 7 a.m. the next day, a phlebotomist, a trained technician who draws blood, arrives at your home. This is home sample collection. She draws two tubes of blood and scans the barcode on each tube, so that each tube is linked to your name.
The tubes travel in a cool box to a lab. Many tests go to a reference laboratory, a large central lab that receives samples from many collection centres and clinics. At the lab, the laboratory information system (LIS) reads each barcode and records the tube's arrival. It tells each machine which tests to run on which tube.
The measuring is done by a clinical lab analyser. One analyser measures the sugar in your blood. Another counts your red cells, white cells and platelets. Each analyser sends its results back to the LIS. The LIS checks them against the normal ranges and against your earlier results. A pathologist, the doctor in charge of the lab, approves the report. By the evening, the report is on your phone and with your doctor. If you have an ABHA number, the health ID of India's national digital health mission, you can link the report to it. A doctor you see later can then read it, with your consent.
Not every test follows this path. Some tests are done right beside the patient and take a few minutes. This is point-of-care testing, such as a haemoglobin check in a village health centre. A molecular test system finds an infection, such as tuberculosis, from the germ's genetic material. And tumour genomic profiling reads the genes of a cancer, sometimes from an ordinary blood sample. Reading genes in this way is called genomics.
All these machines and programs must send results in formats that the doctor's record system can read. Otherwise, someone has to type each result again, and every typed number can be wrong. The ability of health systems to exchange data in a shared format is called interoperability.