There is no established system for the classification of [disease name].

OR

Immune thrombocytopenia may be classified according to associated conditions into groups: primary or secondary.

OR

[Disease name] may be classified into [large number > 6] subtypes based on [classification method 1], [classification method 2], and [classification method 3]. [Disease name] may be classified into several subtypes based on [classification method 1], [classification method 2], and [classification method 3].

OR

Based on the duration of symptoms,Immune thrombocytopenia may be classified as either acute, persistent and chronic.

OR

If the staging system involves specific and characteristic findings and features: According to the [staging system + reference], there are [number] stages of [malignancy name] based on the [finding1], [finding2], and [finding3]. Each stage is assigned a [letter/number1] and a [letter/number2] that designate the [feature1] and [feature2].

OR

The staging of [malignancy name] is based on the [staging system].

OR

There is no established system for the staging of [malignancy name].

Immune thrombocytopenia may be classified according to disease phase into three groups:

• Newly diagnosed ITP (0-3 months)
• Persistent ITP (3-12 moths)
• Chronic ITP ( > 12 months)

Immune Thrombocytopenia may be classified into two subtypes based on associated disease:

• Primary ( isolated thrombocytopenia < 100 <math>\times</math><math>10^{9}</math>/L in the absence of co-existing disorder)
• Secondary ( associated to another disease such as ITP associated with common variable immune deficiency (CVID). ^[1]