Danke, für die Zahlenreihen funktioniert das jetzt.
Ich ahbe noch einen zweiten Aufgabentyp vom Typ "dropdown-Auswahl". Sobald ich hier denselben PHP-Code eingebe funktioniert die gesamte Punkteerfassung nicht mehr. 
Folgende Code nutze ich:
// Definition der Fragen und der korrekten Antworten
$fragen = [
  'A106_01' => 1,  
  'A107_01' => 2,  
  'A108_01' => 3,  
  'A109_01' => 3,
  'A110_01' => 5,
  'A111_01' => 1,
  'A112_01' => 5,
  'A113_01' => 4,
  'A114_01' => 3,
  'A115_01' => 3,
];
// Initialisierung einer Zähler-Variable
$points = 0;
 
// Prüfung aller Fragen in einer Schleife
foreach ($fragen as $variable=>$correct) {
  if (value($variable) == $correct) {
    $points++;
  }
}
// ... oder in einer internen Variable speichern
put('IV04_01', $points);
Ich erhalte folgenden Fehlercode:
Warning (page 17)
The variable A106_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A107_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A108_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A109_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A110_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A111_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A112_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A113_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A114_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Warning (page 17)
The variable A115_01 has not been asked on a previous page during this interview. Therefore value() cannot determine any answer, yet.
Die Variable IV04_01 habe ich bereits in einer Frage definiert