SetSexualDebutAge

The SetSexualDebutAge intervention class sets the age at which an individual will sexually debut — that is, when the individual becomes eligible to enter relationships where coital acts can occur. The intervention expires immediately after it is applied. Note that sexual debut determines when a person can begin forming relationships; the first coital act may occur some time after debut.

When using this intervention, you must set the config parameter Sexual_Debut_Age_Setting_Type to FROM_INTERVENTION. With the default WEIBULL setting, each person's debut age is initialized from a Weibull distribution using the Sexual_Debut_Age_XXX_Weibull_Heterogeneity and Sexual_Debut_Age_XXX_Weibull_Scale parameters. With FROM_INTERVENTION, an individual's debut age is not set unless the SetSexualDebutAge intervention is applied to them.

This intervention is typically used together with ReferenceTrackingEventCoordinatorTrackingConfig and a Tracking_Config of class IsPostDebut to achieve a target fraction of the population debuted by a given age and year. For an example of this approach applied to published research, see Akullian et al. (2025), which used this feature to model cohort-based estimates of the proportion of individuals who had initiated sex by age and sex, and found that increasing age at sexual debut was the largest driver of HIV incidence decline among adolescent girls aged 15–19 in Uganda (PLOS Medicine).

Note

Parameters are case-sensitive. For Boolean parameters, set to 1 for true or 0 for false. Minimum, maximum, or default values of "NA" indicate that those values are not applicable for that parameter.

EMOD does not use true defaults; that is, if the dependency relationships indicate that a parameter is required, you must supply a value for it. However, many of the tools used to work with EMOD will use the default values provided below.

JSON format does not permit comments, but you can add "dummy" parameters to add contextual information to your files. Any keys that are not EMOD parameter names will be ignored by the model.

The table below describes all possible parameters with which this class can be configured. The JSON example that follows shows one potential configuration.

Parameter	Type	Min	Max	Default	Description
Age_Years	float	0	3.40E+38	125	The age, in years, at which the individual receiving this intervention will sexually debut and become eligible to form relationships. If the individual is already older than this value at the time of distribution, they will debut immediately. Only used when Setting_Type is set to USER_SPECIFIED.
Disqualifying_Properties	array of strings	NA	NA	[]	A list of IndividualProperty key:value pairs that cause an intervention to be aborted (persistent interventions will stop being distributed to individuals with these values). See IndividualProperties parameters for more information. Generally used to control the flow of health care access. For example, to prevent the same individual from accessing health care via two different routes at the same time.
Distributed_Event_Trigger	enum	NA	NA	NA	The name of the event to be broadcast when the intervention is distributed to an individual. See Event list for possible values. Custom events can be distributed if they are defined in the config parameter Custom_Individual_Events.
Dont_Allow_Duplicates	boolean	0	1	0	If an individual's container has an intervention, set to true (1) to prevent them from receiving another copy of the intervention. Supported by all intervention classes.
Intervention_Name	string	NA	NA	SetSexualDebutAge	The optional name used to refer to this intervention as a means to differentiate it from others that use the same class.
New_Property_Value	string	NA	NA	""	An optional IndividualProperty key:value pair that will be assigned when the intervention is applied. See IndividualProperties parameters for more information. Generally used to indicate the broad category of health care cascade to which an intervention belongs to prevent individuals from accessing care through multiple pathways. For example, if an individual must already be taking a particular medication to be prescribed a new one.
Setting_Type	enum	NA	NA	CURRENT_AGE	Sets how the sexual debut age is determined for the individual receiving this intervention. Possible values are: CURRENT_AGE The individual will sexually debut immediately at their current age. USER_SPECIFIED The individual will sexually debut at the age specified by Age_Years. If the individual is already older than Age_Years at the time of distribution, they debut immediately.

{
  "Use_Defaults": 1,
  "Events": [
    {
      "Description": "Use reference tracking to debut the correct fraction of 15-19 year old males by year",
      "class": "CampaignEventByYear",
      "Start_Year": 1960.5,
      "Nodeset_Config": {
        "class": "NodeSetAll"
      },
      "Event_Coordinator_Config": {
        "class": "ReferenceTrackingEventCoordinatorTrackingConfig",
        "End_Year": 2050,
        "Update_Period": 30.416667,
        "Time_Value_Map": {
          "Times": [ 1960.5, 2006, 2007, 2008, 2009, 2010 ],
          "Values": [ 0.66, 0.66, 0.68, 0.69, 0.66, 0.65 ]
        },
        "Target_Demographic": "ExplicitAgeRangesAndGender",
        "Target_Gender": "Male",
        "Target_Age_Min": 15,
        "Target_Age_Max": 20,
        "Tracking_Config": {
          "class": "IsPostDebut",
          "Is_Equal_To": 1
        },
        "Intervention_Config": {
          "class": "SetSexualDebutAge",
          "Setting_Type": "CURRENT_AGE"
        }
      }
    }
  ]
}