There were several changes from the DSM-4 to DSM-5 with regards to gender identity disorder:

1. Change the name of gender identity disorder (GID) to gender dysphoria
   This is done because it is less stigmatizing and highlights a conceptual change in the diagnosis.
2. Decouple the diagnosis of GID from the sexual dysfunctions and place it in a separate chapter
   This is done because there is no clear theoretical overlap and it is less stigmatizing.
3. Change in the introductory descriptor to the point A criterion
   This was changed because incongruence is a better descriptor because it does not only pertain to the gender binary (1), gender aligns better with people with a sex disorder (2), there is no need to mention a single potential causal mechanism (3) and there is a clearer distinction between transient GD and persistent GD as time has been added to the descriptor (4).
4. Merging of point A and B criteria from the DSM-IV
   The criteria are merged because the distinction between the two criteria is not supported by factor analytic studies.
5. For children, the A1 criterion is proposed to be a necessary indicator
   This was changed because there are children who meet all the behavioural signs but do not express a desire to be the other sex.
6. For children, there are minor wording changes to the diagnostic criteria
   This was changed to simplify the underlying construct.
7. For adolescents and adults, the proposed diagnostic criteria are polythetic in form and are more detailed
   This was changed to capture a reference to intensity or frequency. The focus now is on a discrepancy between experienced and assigned gender rather than cross-gender identification.
8. Elimination of sexual attraction specifier for adolescents and adults
   This was changed because sexual attraction only plays a minor role in contemporary treatment protocols or decisions.
9. For the point B criterion, there is a change in wording to capture distress, impairment and increased risk of suffering and disability
   This was changed because people who are transitioning may only experience distress when their transitioning process is blocked.
10. Inclusion of a subtype pertaining the presence of a DSD (i.e. intersex)
    This was changed because DSD individuals with gender dysphoria have both similarities and differences with individuals with gender dysphoria with no known DND.
11. Inclusion of a post-transition specifier
    This was changed because many individuals after transitioning do not meet the criteria set for gender dysphoria anymore.

The old introductory descriptor was a strong and persistent cross-gender identification. The A1 criterion refers to repeatedly stated a desire to be or insistence that one is the other sex. A polythetic form refers to the diagnostic criteria sharing a lot of symptoms among each other which are not essential for diagnosis.

There are several validators of gender dysphoria:

1. Antecedent validators
   1. Familial aggregation
      There is a hereditary component of gender identity.
   2. Sociodemographic and cultural factors
      There are more males than females with gender dysphoria and occurs across cultures.
   3. Environmental risk factors
      The boys with gender dysphoria have more brothers (1), are born later than their siblings (i.e. fraternal birth order effect) (2) and have a lower birth weight (3).
2. Concurrent validators
   
   1. Cognitive, emotional, temperamental and personality correlates
      The boys with gender dysphoria perform more poorly on visual-spatial tasks than on verbal tasks and have a lower physical activity level. The girls with gender dysphoria have higher physical activity levels.
   2. Genetics
      There are no known genes linked to gender dysphoria.
   3. Hormonal factors
      There is mixed evidence regarding abnormalities related to molecular genetics and gender dysphoria.
   4. Neuroanatomy
      There may be differences in neuroanatomy in gender dysphoria (e.g. females identifying as males having more similar ‘male’ brain structures) but there is no consensus.
   5. Cerebral dominance and anthropometrics
      There is an elevated rate of left-handedness in males with gender dysphoria, though it is not sure whether it is diagnostic-specific.
   6. Patterns of comorbidity
      The boys with gender dysphoria have elevated rates of internalizing problems and this is more common than externalizing problems. The rates between internalizing and externalizing problems are more equal for girls with gender dysphoria. There is a higher morbidity and suicide rate for people with gender dysphoria.
3. Predictive validators
   
   1. Diagnostic stability
      The persistence rate of gender dysphoria is higher compared to the base rate of gender dysphoria, demonstrating diagnostic stability. Gender-related distress often does not decrease until there is treatment with hormones or surgery.
   2. Course of the condition
      The course of gender dysphoria appears to become more fixed over developmental time with narrowing of plasticity as individuals reach adolescence or adulthood.
   3. Response to treatment
      The successful transition makes the diagnostic criteria not applicable anymore and tends to decrease distress.

People diagnosed with DSD are at a heightened risk for gender dysphoria. Chromosomal females who have been exposed to normal levels of prenatal androgen have an elevated rate of gender dysphoria. This also holds for chromosomal males who are exposed to male-typical prenatal androgen level who are assigned female at birth due to the ambiguity of genitals.