The presence of various compounds in urine has great diagnostic importance. The diagnosis may be based on physical and analytical processes. People from ancient time were diagnosed with various diseases from the observation of urine. The best example is diabetes. In rural areas people are used to discharge urine in the open area instead of in proper urinals. These areas do not have proper healthcare and diagnostic facilities and diagnose diabetes themselves by simply noticing the presence of insects and ants at the urine discharged area. Presence of ants and insects indicates that person discharging urine in the urinated area may have diabetes and needs to consult physician.

Various parameters including: hormones (HCG: for early pregnancy detection), drugs of abuse (cocaine/ barbiturates/ morphine/ marijuana/ opiate), bacterial infections, proteins, blood, nitrite, ketones, urea, creatinine, and medicines are diagnosed with urine specimen.

Urine dipstick is a narrow plastic strip which has several pads (1 to 11) of different colors attached to it. Each small pad represents a component of the test used to interpret urinalysis. The entire strip is dipped in the urine sample and the color changes in each pad are noted. Color change takes place after several seconds to- a few minutes from dipping the strip.

The pads on the dipstick represent the following components in the urine:

• Specific gravity (concentration of urine)
• pH (acidity of urine)
• Protein (mainly albumin)
• Glucose (sugar)
• Ketones (fat metabolism)
• Blood
• Nitrite (suggestive of bacteria in urine)
• Bilirubin (possible liver disease or red blood cell breakdown)
• Urobilinogen (possible liver disease)
• Ascorbic acid
• Leucocytes

Routine testing of urine with multi parameter strips is the first step in diagnosis of a wide range of diseases. Presence or absence of each of these color changes on the strip provides important clues for doctor to make clinical decisions based on the urinalysis results. The main advantage of dipsticks is that they are convenient, easy to interpret, and cost-effective for urinalysis testing. They can be analyzed within minutes of urine collection in the doctor's office or in the emergency room to provide valuable information.

However, what can be learned from a dipstick is limited by the design of the dipstick. The main disadvantage is that the information may not be very accurate as the test is time-sensitive. It also provides limited information about the urine as it is qualitative test and not a quantitative test (for example, it does not give a precise measure of the quantity of abnormality).

The urinary strips are simple, easy to use for the detection of key diagnostic chemical markers in human urine. The reagent pads react with the sample urine to provide a standardized visible color reaction within 30 seconds to one minute depending on the specific panel screen. The color is then visually compared to the included color chart to determine the level of each chemical factor. Test results may provide useful information regarding carbohydrate metabolism, kidney function, acid-base balance, bacteriuria, occult blood, high leukocytes (infection) and other conditions of health.  The strips are ready to use upon removal from the vial and the entire reagent strip is disposable. Each vial comes with a complete abstract on the chemical and biological properties of the test including a color chart for rapid visual diagnosis.

Each vial of urinalysis reagent strips includes a color coded chart. The reactive color of each panel on the test strip is compared to the closest corresponding color on the result chart. The concentration level range for each chemical marker is indicated below each color block on the result chart. As with all tests dealing with color intensity or color matching, it is often recommended to obtain another person's interpretation of the test result. Uses of reagent strips are intended as an initial indication only of elevated chemical markers and not conclusive of a specific diagnosis. Further testing and consultation with a healthcare professional is necessary to confirm the presence of specific disease or health conditions.

Expected values for the normal healthy population and the abnormal population are as follows:

• Glucose: Small amount of glucose¬†may be excreted by the kidney. These amounts are usually below the sensitivity of this test but on occasion may produce a color between the negative and the 1/10 g/dL color blocks. Results of 1/10 g/dL (if consistent) or higher are considered to be significantly abnormal and professional advice should be obtained immediately.
• Protein: A color matching any block greater than Trace indicates significant proteinuria. For urine of high specific gravity, the test area may closely match the Trace color block even though only normal concentration of protein is present. Clinical judgment and advice along with further tests would be required to properly evaluate the significance of consistent Trace readings.
• pH: Normal and abnormal urinary pH may range from 5 to 9. Readings are generally situation specific and should be discussed with your healthcare professional. Generally, certain conditions manifest in low or high consistent pH readings and should be professionally evaluated. First morning urine from healthy individuals will usually range from 5 to 6.
• Bilirubin: Normally, no bilirubin is detectable in urine by even the most sensitive method. Even trace amounts of bilirubin are sufficiently abnormal to require further investigation. A typical color (colors produced which are different than the negative or positive color blocks shown on the color chart) may indicate that bilirubin derived bile pigments are present in the urine sample and are possibly masking the bilirubin reaction.
• Ketone: Detectable levels of ketone may appear in urine during physiological stress conditions such as fasting, pregnancy, and frequent strenuous exercise. In starvation diets, or in other abnormal carbohydrate metabolism situation, ketones appear in the urine in excessively large amounts before serum ketones are elevated.
• Specific gravity: Random urine may vary in specific gravity from 1.003-1.040+. Twenty-four hour urine from normal adults with normal diets and normal fluid intake will have a specific gravity of 0.016-1.02210, in severe renal damage the specific gravity is fixed at 1.010, the value of the glomerular filtrate.
• Blood: Any green spots or green color developing on the reagent area within 40 seconds is significant and the urine should be examined further. Blood is frequently, but not invariably found in the urine of menstruating females.
• Urobilinogen: In a healthy population, the normal urine urobilinogen range obtained with this test is 0.2-1.0 Ehrlich unit/dl. A result of 2.0 EU/dl may be of clinical significance and the same patient sample should be evaluated further.
• Nitrite: The nitrite area will be positive in a proportion of cases of significant infection, depending on how long the urine specimens were retained in the bladder prior to collection.
• Leukocytes: Normal urine specimens generally yield negative results with this test. A trace result may be of questionable clinical significance and it is recommended that the test be repeated using a fresh sample from the same patient. Repeated trace and positive results are of clinical significance.
• Ascorbic acid: The daily urinary output of ascorbic acid varies with the intake. The average urinary output ranges from 20-30 mg/day.