diff --git a/modules/fhir-structure/src/blaze/fhir/spec.clj b/modules/fhir-structure/src/blaze/fhir/spec.clj
index 9f63eb662..ae0f9ea99 100644
--- a/modules/fhir-structure/src/blaze/fhir/spec.clj
+++ b/modules/fhir-structure/src/blaze/fhir/spec.clj
@@ -1,7 +1,7 @@
 (ns blaze.fhir.spec
   (:require
     [blaze.fhir.hash.spec]
-    [blaze.fhir.spec.impl]
+    [blaze.fhir.spec.impl :as impl]
     [blaze.fhir.spec.type :as type]
     [clojure.alpha.spec :as s2]
     [clojure.spec.alpha :as s]
@@ -140,10 +140,10 @@
   from data replaced by their indices."
   {:arglists '([path data])}
   [[elem & elems] data]
-  (if (vector? data)
-    (cons (first (keep-indexed #(when (= %2 elem) %1) data))
-          (when elems (fhir-path-data elems elem)))
-    (cons elem (if elems (fhir-path-data elems (get data elem)) []))))
+  (if (keyword? elem)
+    (cons elem (if elems (fhir-path-data elems (get data elem)) []))
+    (cons (first (keep-indexed #(when (= %2 elem) %1) (impl/ensure-coll data)))
+          (when elems (fhir-path-data elems elem)))))
 
 
 (defn fhir-path
@@ -151,13 +151,15 @@
   the given path."
   [path resource]
   (->> (fhir-path-data path resource)
-       (reduce (fn [list elem] (if (keyword? elem)
-                                 (conj list (name elem))
-                                 (update list
-                                         (dec (count list))
-                                         str
-                                         (format "[%d]" elem))))
-               [])
+       (reduce
+         (fn [list elem]
+           (if (keyword? elem)
+             (conj list (name elem))
+             (update list
+                     (dec (count list))
+                     str
+                     (format "[%d]" elem))))
+         [])
        (str/join ".")))
 
 
@@ -275,7 +277,7 @@
 
 
 (defn primitive-val?
-  ""
+  "Returns true if `x` is a primitive FHIR value."
   [x]
   (when-let [fhir-type (fhir-type x)]
     (and (= "fhir" (namespace fhir-type))
diff --git a/modules/fhir-structure/src/blaze/fhir/spec/impl.clj b/modules/fhir-structure/src/blaze/fhir/spec/impl.clj
index 8c252062d..b6086ab95 100644
--- a/modules/fhir-structure/src/blaze/fhir/spec/impl.clj
+++ b/modules/fhir-structure/src/blaze/fhir/spec/impl.clj
@@ -288,7 +288,7 @@
               [(keyword (name key))
                (if (= "1" max)
                  key
-                 (if (= :xml modifier)
+                 (if (#{:json :xml} modifier)
                    `(s/and
                       (s/conformer ensure-coll identity)
                       (s/coll-of ~key))
@@ -391,7 +391,7 @@
     (vector? old)
     (conj old element)
     old
-    (conj [old] element)
+    [old element]
     :else
     element))
 
diff --git a/modules/fhir-structure/test/blaze/fhir/spec/impl_test.clj b/modules/fhir-structure/test/blaze/fhir/spec/impl_test.clj
index 0837b93ca..8968fe16e 100644
--- a/modules/fhir-structure/test/blaze/fhir/spec/impl_test.clj
+++ b/modules/fhir-structure/test/blaze/fhir/spec/impl_test.clj
@@ -353,8 +353,10 @@
              :type :fhir.json.Bundle/type
              :timestamp :fhir.json.Bundle/timestamp
              :total :fhir.json.Bundle/total
-             :link (s2/coll-of :fhir.json.Bundle/link)
-             :entry (s2/coll-of :fhir.json.Bundle/entry)
+             :link (s2/and (s2/conformer impl/ensure-coll identity)
+                           (s2/coll-of :fhir.json.Bundle/link))
+             :entry (s2/and (s2/conformer impl/ensure-coll identity)
+                            (s2/coll-of :fhir.json.Bundle/entry))
              :signature :fhir.json.Bundle/signature})))
 
   (testing "JSON representation of Bundle.id"
@@ -376,9 +378,12 @@
       := `(s2/and
             (s2/schema
               {:id :fhir.json.Bundle.entry/id
-               :extension (s2/coll-of :fhir.json.Bundle.entry/extension)
-               :modifierExtension (s2/coll-of :fhir.json.Bundle.entry/modifierExtension)
-               :link (s2/coll-of :fhir.json.Bundle.entry/link)
+               :extension (s2/and (s2/conformer impl/ensure-coll identity)
+                                  (s2/coll-of :fhir.json.Bundle.entry/extension))
+               :modifierExtension (s2/and (s2/conformer impl/ensure-coll identity)
+                                          (s2/coll-of :fhir.json.Bundle.entry/modifierExtension))
+               :link (s2/and (s2/conformer impl/ensure-coll identity)
+                             (s2/coll-of :fhir.json.Bundle.entry/link))
                :fullUrl :fhir.json.Bundle.entry/fullUrl
                :resource :fhir.json.Bundle.entry/resource
                :search :fhir.json.Bundle.entry/search
diff --git a/modules/fhir-structure/test/blaze/fhir/spec_test.clj b/modules/fhir-structure/test/blaze/fhir/spec_test.clj
index e0377f46d..ad2126250 100644
--- a/modules/fhir-structure/test/blaze/fhir/spec_test.clj
+++ b/modules/fhir-structure/test/blaze/fhir/spec_test.clj
@@ -467,8 +467,8 @@
       [:fhir/issues 0 :fhir.issues/severity] := "error"
       [:fhir/issues 0 :fhir.issues/code] := "invariant"
       [:fhir/issues 0 :fhir.issues/diagnostics] :=
-      "Error on value ``. Expected type is `JSON array`."
-      [:fhir/issues 0 :fhir.issues/expression] := "contact"))
+      "Error on value ``. Expected type is `Patient.contact`."
+      [:fhir/issues 0 :fhir.issues/expression] := "contact[0]"))
 
   (testing "invalid non-primitive element"
     (given (fhir-spec/explain-data-json {:resourceType "Patient"
@@ -476,8 +476,8 @@
       [:fhir/issues 0 :fhir.issues/severity] := "error"
       [:fhir/issues 0 :fhir.issues/code] := "invariant"
       [:fhir/issues 0 :fhir.issues/diagnostics] :=
-      "Error on value ``. Expected type is `JSON array`."
-      [:fhir/issues 0 :fhir.issues/expression] := "name"))
+      "Error on value ``. Expected type is `HumanName`."
+      [:fhir/issues 0 :fhir.issues/expression] := "name[0]"))
 
   (testing "Include namespace part if more than fhir"
     (given (fhir-spec/explain-data-json {:resourceType "Patient"
@@ -837,3 +837,10 @@
     (testing "XML"
       (is (= xhtml-element
              (s2/unform :fhir.xml/xhtml #fhir/xhtml"<div xmlns=\"http://www.w3.org/1999/xhtml\"><p>FHIR is cool.</p></div>"))))))
+
+
+(deftest primitive-val?
+  (are [x] (fhir-spec/primitive-val? x)
+    "foo"
+    1
+    #fhir/code"bar"))