Syntax

Clinical work flow

The clinical workflow is a series of events. In lympha this is formulated as statements divided by ->. A series of statements ends with semicolon as follows:

statement -> statement -> statement ;

The name of the statement consists of one word, made of letters a-z, A-Z, digits 0-9, full stop (.), question mark, hyphen (-) and underscore (_).

Some events are procedures that should be executed. In lympha, these events are called procedures. Some events do not directly involve the patient, but data derived from diagnostics. Those events are called factors. Hence there are two types of statements in lympha: procedures and factors.

Differences between procedrues and factors

The name of a procedure always ends with a full stop (.) meanwhile, factors always end with a question mark (?).

Depending on if a procedure should be executed or not, it has a value of 1 or 0. By default, all procedures have the value set to 1.

The value of a factor can be declared in three ways:

• Make it equal to a real number (ℝ). Example:

  body_temperature_in_C? = 35.8 ;
  

• The value of the factor can also be dependent upon other factors. These dependent factors are called binary factors. The binary factor name in question is followed by one equal sign (=). Then follows a tipping point. After that, there is an operator. Below are valid operators listed:

  Valid rational operators

  relational operator	read as
  ==	if and only if (≡)
  >	greater than
  >=	greater than or equal (≥)
  <	lesser than
  <=	less than or equal (≤)
  !=	not equal to (≠)

  After the operator follows either the name of a non-binary factor or a series of binary factors.

  • In the case where the binary factor depends on a non-binary factor:

    binary-factor = tipping-point operator non-binary-factor ;
    

    Example:

    hypothermia? = 36 < body_temperature_in_C? ;
    

  • In the case where the binary factor depends on a non-binary factor:

    binary-factor = tipping-point operator |{non-binary-factors}|
    

    Example:

    resp? = 1 < |{tachypnea?, pCO2_blood_less4.3?}| ;
    SIRS? = 2 =< |{ hypothermia?, temp_above_38?, HR_greater_90?, resp?, wbc_less4000?, wbc_greater12000?  }| ;
    

In order for a procedure or a binary-factor to get the value 1, at least one parent-statement must have the value 1.