A diagnostic device for diagnosing a state of a subject based on a ratio or a difference between a color intensity of a first test portion and a color intensity of a second test portion in a reaction unit receiving a sample therein, wherein the device includes: the reaction unit receiving the sample therein and having two or more test portions; and a diagnosis unit for diagnosing the state of the subject based on the ratio or the difference between the color intensity of the first test portion and the color intensity of the second test portion; wherein the diagnosis unit is configured to diagnose a pregnancy related state of the subject, based on the ratio or the difference between the color intensity of the first test portion and the color intensity of the second test portion, wherein the color intensity of the first test portion is higher as an analyte concentration increases, and the color intensity of the second test portion is lower as the analyte concentration increases, and wherein the color intensity of the first test portion occurs based on a sandwich immunoassay scheme, and the color intensity of the second test portion occurs based on a competitive immunoassay scheme; wherein the diagnosis unit is configured to: determine, for a first sample, a first ratio between a color intensity of the first test portion and a color intensity of the second test portion at a first time-point; determine, for a second sample, a second ratio between a color intensity of the first test portion and a color intensity of the second test portion at a second time-point; and diagnose the pregnancy related state of the subject based on the first ratio and the second ratio, wherein the second time-point is temporally subsequent to the first time-point. wherein the device includes: the reaction unit receiving the sample therein and having two or more test portions; and a diagnosis unit for diagnosing the state of the subject based on the ratio or the difference between the color intensity of the first test portion and the color intensity of the second test portion; the reaction unit receiving the sample therein and having two or more test portions; and a diagnosis unit for diagnosing the state of the subject based on the ratio or the difference between the color intensity of the first test portion and the color intensity of the second test portion; wherein the diagnosis unit is configured to diagnose a pregnancy related state of the subject, based on the ratio or the difference between the color intensity of the first test portion and the color intensity of the second test portion, wherein the color intensity of the first test portion is higher as an analyte concentration increases, and the color intensity of the second test portion is lower as the analyte concentration increases, and wherein the color intensity of the first test portion occurs based on a sandwich immunoassay scheme, and the color intensity of the second test portion occurs based on a competitive immunoassay scheme; wherein the diagnosis unit is configured to: determine, for a first sample, a first ratio between a color intensity of the first test portion and a color intensity of the second test portion at a first time-point; determine, for a second sample, a second ratio between a color intensity of the first test portion and a color intensity of the second test portion at a second time-point; and diagnose the pregnancy related state of the subject based on the first ratio and the second ratio, determine, for a first sample, a first ratio between a color intensity of the first test portion and a color intensity of the second test portion at a first time-point; determine, for a second sample, a second ratio between a color intensity of the first test portion and a color intensity of the second test portion at a second time-point; and diagnose the pregnancy related state of the subject based on the first ratio and the second ratio, wherein the second time-point is temporally subsequent to the first time-point.