diff --git a/src/bam/overlap.jl b/src/bam/overlap.jl
index 186ff59..0e184c9 100644
--- a/src/bam/overlap.jl
+++ b/src/bam/overlap.jl
@@ -67,7 +67,8 @@ function Base.iterate(iter::OverlapIterator, state)
             c = compare_intervals(state.record, (state.refindex, iter.interval))
             if c == 0
                 return copy(state.record), state
-            elseif c > 0
+            end
+            if c > 0
                 # no more overlapping records in this chunk since records are sorted
                 break
             end
diff --git a/src/bam/reader.jl b/src/bam/reader.jl
index 301246c..9ec5d0d 100644
--- a/src/bam/reader.jl
+++ b/src/bam/reader.jl
@@ -30,10 +30,8 @@ end
 function Reader(input::IO; index=nothing)
     if isa(index, AbstractString)
         index = BAI(index)
-    else
-        if index != nothing
-            error("unrecognizable index argument")
-        end
+    elseif index != nothing
+        error("unrecognizable index argument")
     end
     reader = init_bam_reader(input)
     reader.index = index
diff --git a/src/bam/record.jl b/src/bam/record.jl
index d0bde20..ad9c6f1 100644
--- a/src/bam/record.jl
+++ b/src/bam/record.jl
@@ -163,7 +163,8 @@ function checked_refid(record::Record)
     id = refid(record)
     if id == 0
         throw(ArgumentError("record is not mapped"))
-    elseif !isdefined(record, :reader)
+    end
+    if !isdefined(record, :reader)
         throw(ArgumentError("reader is not defined"))
     end
     return id